1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * trace_events_hist - trace event hist triggers 4 * 5 * Copyright (C) 2015 Tom Zanussi <tom.zanussi@linux.intel.com> 6 */ 7 8 #include <linux/module.h> 9 #include <linux/kallsyms.h> 10 #include <linux/mutex.h> 11 #include <linux/slab.h> 12 #include <linux/stacktrace.h> 13 #include <linux/rculist.h> 14 #include <linux/tracefs.h> 15 16 #include "tracing_map.h" 17 #include "trace.h" 18 #include "trace_dynevent.h" 19 20 #define SYNTH_SYSTEM "synthetic" 21 #define SYNTH_FIELDS_MAX 16 22 23 #define STR_VAR_LEN_MAX 32 /* must be multiple of sizeof(u64) */ 24 25 struct hist_field; 26 27 typedef u64 (*hist_field_fn_t) (struct hist_field *field, 28 struct tracing_map_elt *elt, 29 struct ring_buffer_event *rbe, 30 void *event); 31 32 #define HIST_FIELD_OPERANDS_MAX 2 33 #define HIST_FIELDS_MAX (TRACING_MAP_FIELDS_MAX + TRACING_MAP_VARS_MAX) 34 #define HIST_ACTIONS_MAX 8 35 36 enum field_op_id { 37 FIELD_OP_NONE, 38 FIELD_OP_PLUS, 39 FIELD_OP_MINUS, 40 FIELD_OP_UNARY_MINUS, 41 }; 42 43 /* 44 * A hist_var (histogram variable) contains variable information for 45 * hist_fields having the HIST_FIELD_FL_VAR or HIST_FIELD_FL_VAR_REF 46 * flag set. A hist_var has a variable name e.g. ts0, and is 47 * associated with a given histogram trigger, as specified by 48 * hist_data. The hist_var idx is the unique index assigned to the 49 * variable by the hist trigger's tracing_map. The idx is what is 50 * used to set a variable's value and, by a variable reference, to 51 * retrieve it. 52 */ 53 struct hist_var { 54 char *name; 55 struct hist_trigger_data *hist_data; 56 unsigned int idx; 57 }; 58 59 struct hist_field { 60 struct ftrace_event_field *field; 61 unsigned long flags; 62 hist_field_fn_t fn; 63 unsigned int size; 64 unsigned int offset; 65 unsigned int is_signed; 66 const char *type; 67 struct hist_field *operands[HIST_FIELD_OPERANDS_MAX]; 68 struct hist_trigger_data *hist_data; 69 70 /* 71 * Variable fields contain variable-specific info in var. 72 */ 73 struct hist_var var; 74 enum field_op_id operator; 75 char *system; 76 char *event_name; 77 78 /* 79 * The name field is used for EXPR and VAR_REF fields. VAR 80 * fields contain the variable name in var.name. 81 */ 82 char *name; 83 84 /* 85 * When a histogram trigger is hit, if it has any references 86 * to variables, the values of those variables are collected 87 * into a var_ref_vals array by resolve_var_refs(). The 88 * current value of each variable is read from the tracing_map 89 * using the hist field's hist_var.idx and entered into the 90 * var_ref_idx entry i.e. var_ref_vals[var_ref_idx]. 91 */ 92 unsigned int var_ref_idx; 93 bool read_once; 94 }; 95 96 static u64 hist_field_none(struct hist_field *field, 97 struct tracing_map_elt *elt, 98 struct ring_buffer_event *rbe, 99 void *event) 100 { 101 return 0; 102 } 103 104 static u64 hist_field_counter(struct hist_field *field, 105 struct tracing_map_elt *elt, 106 struct ring_buffer_event *rbe, 107 void *event) 108 { 109 return 1; 110 } 111 112 static u64 hist_field_string(struct hist_field *hist_field, 113 struct tracing_map_elt *elt, 114 struct ring_buffer_event *rbe, 115 void *event) 116 { 117 char *addr = (char *)(event + hist_field->field->offset); 118 119 return (u64)(unsigned long)addr; 120 } 121 122 static u64 hist_field_dynstring(struct hist_field *hist_field, 123 struct tracing_map_elt *elt, 124 struct ring_buffer_event *rbe, 125 void *event) 126 { 127 u32 str_item = *(u32 *)(event + hist_field->field->offset); 128 int str_loc = str_item & 0xffff; 129 char *addr = (char *)(event + str_loc); 130 131 return (u64)(unsigned long)addr; 132 } 133 134 static u64 hist_field_pstring(struct hist_field *hist_field, 135 struct tracing_map_elt *elt, 136 struct ring_buffer_event *rbe, 137 void *event) 138 { 139 char **addr = (char **)(event + hist_field->field->offset); 140 141 return (u64)(unsigned long)*addr; 142 } 143 144 static u64 hist_field_log2(struct hist_field *hist_field, 145 struct tracing_map_elt *elt, 146 struct ring_buffer_event *rbe, 147 void *event) 148 { 149 struct hist_field *operand = hist_field->operands[0]; 150 151 u64 val = operand->fn(operand, elt, rbe, event); 152 153 return (u64) ilog2(roundup_pow_of_two(val)); 154 } 155 156 static u64 hist_field_plus(struct hist_field *hist_field, 157 struct tracing_map_elt *elt, 158 struct ring_buffer_event *rbe, 159 void *event) 160 { 161 struct hist_field *operand1 = hist_field->operands[0]; 162 struct hist_field *operand2 = hist_field->operands[1]; 163 164 u64 val1 = operand1->fn(operand1, elt, rbe, event); 165 u64 val2 = operand2->fn(operand2, elt, rbe, event); 166 167 return val1 + val2; 168 } 169 170 static u64 hist_field_minus(struct hist_field *hist_field, 171 struct tracing_map_elt *elt, 172 struct ring_buffer_event *rbe, 173 void *event) 174 { 175 struct hist_field *operand1 = hist_field->operands[0]; 176 struct hist_field *operand2 = hist_field->operands[1]; 177 178 u64 val1 = operand1->fn(operand1, elt, rbe, event); 179 u64 val2 = operand2->fn(operand2, elt, rbe, event); 180 181 return val1 - val2; 182 } 183 184 static u64 hist_field_unary_minus(struct hist_field *hist_field, 185 struct tracing_map_elt *elt, 186 struct ring_buffer_event *rbe, 187 void *event) 188 { 189 struct hist_field *operand = hist_field->operands[0]; 190 191 s64 sval = (s64)operand->fn(operand, elt, rbe, event); 192 u64 val = (u64)-sval; 193 194 return val; 195 } 196 197 #define DEFINE_HIST_FIELD_FN(type) \ 198 static u64 hist_field_##type(struct hist_field *hist_field, \ 199 struct tracing_map_elt *elt, \ 200 struct ring_buffer_event *rbe, \ 201 void *event) \ 202 { \ 203 type *addr = (type *)(event + hist_field->field->offset); \ 204 \ 205 return (u64)(unsigned long)*addr; \ 206 } 207 208 DEFINE_HIST_FIELD_FN(s64); 209 DEFINE_HIST_FIELD_FN(u64); 210 DEFINE_HIST_FIELD_FN(s32); 211 DEFINE_HIST_FIELD_FN(u32); 212 DEFINE_HIST_FIELD_FN(s16); 213 DEFINE_HIST_FIELD_FN(u16); 214 DEFINE_HIST_FIELD_FN(s8); 215 DEFINE_HIST_FIELD_FN(u8); 216 217 #define for_each_hist_field(i, hist_data) \ 218 for ((i) = 0; (i) < (hist_data)->n_fields; (i)++) 219 220 #define for_each_hist_val_field(i, hist_data) \ 221 for ((i) = 0; (i) < (hist_data)->n_vals; (i)++) 222 223 #define for_each_hist_key_field(i, hist_data) \ 224 for ((i) = (hist_data)->n_vals; (i) < (hist_data)->n_fields; (i)++) 225 226 #define HIST_STACKTRACE_DEPTH 16 227 #define HIST_STACKTRACE_SIZE (HIST_STACKTRACE_DEPTH * sizeof(unsigned long)) 228 #define HIST_STACKTRACE_SKIP 5 229 230 #define HITCOUNT_IDX 0 231 #define HIST_KEY_SIZE_MAX (MAX_FILTER_STR_VAL + HIST_STACKTRACE_SIZE) 232 233 enum hist_field_flags { 234 HIST_FIELD_FL_HITCOUNT = 1 << 0, 235 HIST_FIELD_FL_KEY = 1 << 1, 236 HIST_FIELD_FL_STRING = 1 << 2, 237 HIST_FIELD_FL_HEX = 1 << 3, 238 HIST_FIELD_FL_SYM = 1 << 4, 239 HIST_FIELD_FL_SYM_OFFSET = 1 << 5, 240 HIST_FIELD_FL_EXECNAME = 1 << 6, 241 HIST_FIELD_FL_SYSCALL = 1 << 7, 242 HIST_FIELD_FL_STACKTRACE = 1 << 8, 243 HIST_FIELD_FL_LOG2 = 1 << 9, 244 HIST_FIELD_FL_TIMESTAMP = 1 << 10, 245 HIST_FIELD_FL_TIMESTAMP_USECS = 1 << 11, 246 HIST_FIELD_FL_VAR = 1 << 12, 247 HIST_FIELD_FL_EXPR = 1 << 13, 248 HIST_FIELD_FL_VAR_REF = 1 << 14, 249 HIST_FIELD_FL_CPU = 1 << 15, 250 HIST_FIELD_FL_ALIAS = 1 << 16, 251 }; 252 253 struct var_defs { 254 unsigned int n_vars; 255 char *name[TRACING_MAP_VARS_MAX]; 256 char *expr[TRACING_MAP_VARS_MAX]; 257 }; 258 259 struct hist_trigger_attrs { 260 char *keys_str; 261 char *vals_str; 262 char *sort_key_str; 263 char *name; 264 char *clock; 265 bool pause; 266 bool cont; 267 bool clear; 268 bool ts_in_usecs; 269 unsigned int map_bits; 270 271 char *assignment_str[TRACING_MAP_VARS_MAX]; 272 unsigned int n_assignments; 273 274 char *action_str[HIST_ACTIONS_MAX]; 275 unsigned int n_actions; 276 277 struct var_defs var_defs; 278 }; 279 280 struct field_var { 281 struct hist_field *var; 282 struct hist_field *val; 283 }; 284 285 struct field_var_hist { 286 struct hist_trigger_data *hist_data; 287 char *cmd; 288 }; 289 290 struct hist_trigger_data { 291 struct hist_field *fields[HIST_FIELDS_MAX]; 292 unsigned int n_vals; 293 unsigned int n_keys; 294 unsigned int n_fields; 295 unsigned int n_vars; 296 unsigned int key_size; 297 struct tracing_map_sort_key sort_keys[TRACING_MAP_SORT_KEYS_MAX]; 298 unsigned int n_sort_keys; 299 struct trace_event_file *event_file; 300 struct hist_trigger_attrs *attrs; 301 struct tracing_map *map; 302 bool enable_timestamps; 303 bool remove; 304 struct hist_field *var_refs[TRACING_MAP_VARS_MAX]; 305 unsigned int n_var_refs; 306 307 struct action_data *actions[HIST_ACTIONS_MAX]; 308 unsigned int n_actions; 309 310 struct field_var *field_vars[SYNTH_FIELDS_MAX]; 311 unsigned int n_field_vars; 312 unsigned int n_field_var_str; 313 struct field_var_hist *field_var_hists[SYNTH_FIELDS_MAX]; 314 unsigned int n_field_var_hists; 315 316 struct field_var *save_vars[SYNTH_FIELDS_MAX]; 317 unsigned int n_save_vars; 318 unsigned int n_save_var_str; 319 }; 320 321 static int synth_event_create(int argc, const char **argv); 322 static int synth_event_show(struct seq_file *m, struct dyn_event *ev); 323 static int synth_event_release(struct dyn_event *ev); 324 static bool synth_event_is_busy(struct dyn_event *ev); 325 static bool synth_event_match(const char *system, const char *event, 326 struct dyn_event *ev); 327 328 static struct dyn_event_operations synth_event_ops = { 329 .create = synth_event_create, 330 .show = synth_event_show, 331 .is_busy = synth_event_is_busy, 332 .free = synth_event_release, 333 .match = synth_event_match, 334 }; 335 336 struct synth_field { 337 char *type; 338 char *name; 339 size_t size; 340 bool is_signed; 341 bool is_string; 342 }; 343 344 struct synth_event { 345 struct dyn_event devent; 346 int ref; 347 char *name; 348 struct synth_field **fields; 349 unsigned int n_fields; 350 unsigned int n_u64; 351 struct trace_event_class class; 352 struct trace_event_call call; 353 struct tracepoint *tp; 354 }; 355 356 static bool is_synth_event(struct dyn_event *ev) 357 { 358 return ev->ops == &synth_event_ops; 359 } 360 361 static struct synth_event *to_synth_event(struct dyn_event *ev) 362 { 363 return container_of(ev, struct synth_event, devent); 364 } 365 366 static bool synth_event_is_busy(struct dyn_event *ev) 367 { 368 struct synth_event *event = to_synth_event(ev); 369 370 return event->ref != 0; 371 } 372 373 static bool synth_event_match(const char *system, const char *event, 374 struct dyn_event *ev) 375 { 376 struct synth_event *sev = to_synth_event(ev); 377 378 return strcmp(sev->name, event) == 0 && 379 (!system || strcmp(system, SYNTH_SYSTEM) == 0); 380 } 381 382 struct action_data; 383 384 typedef void (*action_fn_t) (struct hist_trigger_data *hist_data, 385 struct tracing_map_elt *elt, void *rec, 386 struct ring_buffer_event *rbe, void *key, 387 struct action_data *data, u64 *var_ref_vals); 388 389 typedef bool (*check_track_val_fn_t) (u64 track_val, u64 var_val); 390 391 enum handler_id { 392 HANDLER_ONMATCH = 1, 393 HANDLER_ONMAX, 394 HANDLER_ONCHANGE, 395 }; 396 397 enum action_id { 398 ACTION_SAVE = 1, 399 ACTION_TRACE, 400 ACTION_SNAPSHOT, 401 }; 402 403 struct action_data { 404 enum handler_id handler; 405 enum action_id action; 406 char *action_name; 407 action_fn_t fn; 408 409 unsigned int n_params; 410 char *params[SYNTH_FIELDS_MAX]; 411 412 /* 413 * When a histogram trigger is hit, the values of any 414 * references to variables, including variables being passed 415 * as parameters to synthetic events, are collected into a 416 * var_ref_vals array. This var_ref_idx is the index of the 417 * first param in the array to be passed to the synthetic 418 * event invocation. 419 */ 420 unsigned int var_ref_idx; 421 struct synth_event *synth_event; 422 bool use_trace_keyword; 423 char *synth_event_name; 424 425 union { 426 struct { 427 char *event; 428 char *event_system; 429 } match_data; 430 431 struct { 432 /* 433 * var_str contains the $-unstripped variable 434 * name referenced by var_ref, and used when 435 * printing the action. Because var_ref 436 * creation is deferred to create_actions(), 437 * we need a per-action way to save it until 438 * then, thus var_str. 439 */ 440 char *var_str; 441 442 /* 443 * var_ref refers to the variable being 444 * tracked e.g onmax($var). 445 */ 446 struct hist_field *var_ref; 447 448 /* 449 * track_var contains the 'invisible' tracking 450 * variable created to keep the current 451 * e.g. max value. 452 */ 453 struct hist_field *track_var; 454 455 check_track_val_fn_t check_val; 456 action_fn_t save_data; 457 } track_data; 458 }; 459 }; 460 461 struct track_data { 462 u64 track_val; 463 bool updated; 464 465 unsigned int key_len; 466 void *key; 467 struct tracing_map_elt elt; 468 469 struct action_data *action_data; 470 struct hist_trigger_data *hist_data; 471 }; 472 473 struct hist_elt_data { 474 char *comm; 475 u64 *var_ref_vals; 476 char *field_var_str[SYNTH_FIELDS_MAX]; 477 }; 478 479 struct snapshot_context { 480 struct tracing_map_elt *elt; 481 void *key; 482 }; 483 484 static void track_data_free(struct track_data *track_data) 485 { 486 struct hist_elt_data *elt_data; 487 488 if (!track_data) 489 return; 490 491 kfree(track_data->key); 492 493 elt_data = track_data->elt.private_data; 494 if (elt_data) { 495 kfree(elt_data->comm); 496 kfree(elt_data); 497 } 498 499 kfree(track_data); 500 } 501 502 static struct track_data *track_data_alloc(unsigned int key_len, 503 struct action_data *action_data, 504 struct hist_trigger_data *hist_data) 505 { 506 struct track_data *data = kzalloc(sizeof(*data), GFP_KERNEL); 507 struct hist_elt_data *elt_data; 508 509 if (!data) 510 return ERR_PTR(-ENOMEM); 511 512 data->key = kzalloc(key_len, GFP_KERNEL); 513 if (!data->key) { 514 track_data_free(data); 515 return ERR_PTR(-ENOMEM); 516 } 517 518 data->key_len = key_len; 519 data->action_data = action_data; 520 data->hist_data = hist_data; 521 522 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL); 523 if (!elt_data) { 524 track_data_free(data); 525 return ERR_PTR(-ENOMEM); 526 } 527 data->elt.private_data = elt_data; 528 529 elt_data->comm = kzalloc(TASK_COMM_LEN, GFP_KERNEL); 530 if (!elt_data->comm) { 531 track_data_free(data); 532 return ERR_PTR(-ENOMEM); 533 } 534 535 return data; 536 } 537 538 static char last_hist_cmd[MAX_FILTER_STR_VAL]; 539 static char hist_err_str[MAX_FILTER_STR_VAL]; 540 541 static void last_cmd_set(char *str) 542 { 543 if (!str) 544 return; 545 546 strncpy(last_hist_cmd, str, MAX_FILTER_STR_VAL - 1); 547 } 548 549 static void hist_err(char *str, char *var) 550 { 551 int maxlen = MAX_FILTER_STR_VAL - 1; 552 553 if (!str) 554 return; 555 556 if (strlen(hist_err_str)) 557 return; 558 559 if (!var) 560 var = ""; 561 562 if (strlen(hist_err_str) + strlen(str) + strlen(var) > maxlen) 563 return; 564 565 strcat(hist_err_str, str); 566 strcat(hist_err_str, var); 567 } 568 569 static void hist_err_event(char *str, char *system, char *event, char *var) 570 { 571 char err[MAX_FILTER_STR_VAL]; 572 573 if (system && var) 574 snprintf(err, MAX_FILTER_STR_VAL, "%s.%s.%s", system, event, var); 575 else if (system) 576 snprintf(err, MAX_FILTER_STR_VAL, "%s.%s", system, event); 577 else 578 strscpy(err, var, MAX_FILTER_STR_VAL); 579 580 hist_err(str, err); 581 } 582 583 static void hist_err_clear(void) 584 { 585 hist_err_str[0] = '\0'; 586 } 587 588 static bool have_hist_err(void) 589 { 590 if (strlen(hist_err_str)) 591 return true; 592 593 return false; 594 } 595 596 struct synth_trace_event { 597 struct trace_entry ent; 598 u64 fields[]; 599 }; 600 601 static int synth_event_define_fields(struct trace_event_call *call) 602 { 603 struct synth_trace_event trace; 604 int offset = offsetof(typeof(trace), fields); 605 struct synth_event *event = call->data; 606 unsigned int i, size, n_u64; 607 char *name, *type; 608 bool is_signed; 609 int ret = 0; 610 611 for (i = 0, n_u64 = 0; i < event->n_fields; i++) { 612 size = event->fields[i]->size; 613 is_signed = event->fields[i]->is_signed; 614 type = event->fields[i]->type; 615 name = event->fields[i]->name; 616 ret = trace_define_field(call, type, name, offset, size, 617 is_signed, FILTER_OTHER); 618 if (ret) 619 break; 620 621 if (event->fields[i]->is_string) { 622 offset += STR_VAR_LEN_MAX; 623 n_u64 += STR_VAR_LEN_MAX / sizeof(u64); 624 } else { 625 offset += sizeof(u64); 626 n_u64++; 627 } 628 } 629 630 event->n_u64 = n_u64; 631 632 return ret; 633 } 634 635 static bool synth_field_signed(char *type) 636 { 637 if (str_has_prefix(type, "u")) 638 return false; 639 640 return true; 641 } 642 643 static int synth_field_is_string(char *type) 644 { 645 if (strstr(type, "char[") != NULL) 646 return true; 647 648 return false; 649 } 650 651 static int synth_field_string_size(char *type) 652 { 653 char buf[4], *end, *start; 654 unsigned int len; 655 int size, err; 656 657 start = strstr(type, "char["); 658 if (start == NULL) 659 return -EINVAL; 660 start += sizeof("char[") - 1; 661 662 end = strchr(type, ']'); 663 if (!end || end < start) 664 return -EINVAL; 665 666 len = end - start; 667 if (len > 3) 668 return -EINVAL; 669 670 strncpy(buf, start, len); 671 buf[len] = '\0'; 672 673 err = kstrtouint(buf, 0, &size); 674 if (err) 675 return err; 676 677 if (size > STR_VAR_LEN_MAX) 678 return -EINVAL; 679 680 return size; 681 } 682 683 static int synth_field_size(char *type) 684 { 685 int size = 0; 686 687 if (strcmp(type, "s64") == 0) 688 size = sizeof(s64); 689 else if (strcmp(type, "u64") == 0) 690 size = sizeof(u64); 691 else if (strcmp(type, "s32") == 0) 692 size = sizeof(s32); 693 else if (strcmp(type, "u32") == 0) 694 size = sizeof(u32); 695 else if (strcmp(type, "s16") == 0) 696 size = sizeof(s16); 697 else if (strcmp(type, "u16") == 0) 698 size = sizeof(u16); 699 else if (strcmp(type, "s8") == 0) 700 size = sizeof(s8); 701 else if (strcmp(type, "u8") == 0) 702 size = sizeof(u8); 703 else if (strcmp(type, "char") == 0) 704 size = sizeof(char); 705 else if (strcmp(type, "unsigned char") == 0) 706 size = sizeof(unsigned char); 707 else if (strcmp(type, "int") == 0) 708 size = sizeof(int); 709 else if (strcmp(type, "unsigned int") == 0) 710 size = sizeof(unsigned int); 711 else if (strcmp(type, "long") == 0) 712 size = sizeof(long); 713 else if (strcmp(type, "unsigned long") == 0) 714 size = sizeof(unsigned long); 715 else if (strcmp(type, "pid_t") == 0) 716 size = sizeof(pid_t); 717 else if (synth_field_is_string(type)) 718 size = synth_field_string_size(type); 719 720 return size; 721 } 722 723 static const char *synth_field_fmt(char *type) 724 { 725 const char *fmt = "%llu"; 726 727 if (strcmp(type, "s64") == 0) 728 fmt = "%lld"; 729 else if (strcmp(type, "u64") == 0) 730 fmt = "%llu"; 731 else if (strcmp(type, "s32") == 0) 732 fmt = "%d"; 733 else if (strcmp(type, "u32") == 0) 734 fmt = "%u"; 735 else if (strcmp(type, "s16") == 0) 736 fmt = "%d"; 737 else if (strcmp(type, "u16") == 0) 738 fmt = "%u"; 739 else if (strcmp(type, "s8") == 0) 740 fmt = "%d"; 741 else if (strcmp(type, "u8") == 0) 742 fmt = "%u"; 743 else if (strcmp(type, "char") == 0) 744 fmt = "%d"; 745 else if (strcmp(type, "unsigned char") == 0) 746 fmt = "%u"; 747 else if (strcmp(type, "int") == 0) 748 fmt = "%d"; 749 else if (strcmp(type, "unsigned int") == 0) 750 fmt = "%u"; 751 else if (strcmp(type, "long") == 0) 752 fmt = "%ld"; 753 else if (strcmp(type, "unsigned long") == 0) 754 fmt = "%lu"; 755 else if (strcmp(type, "pid_t") == 0) 756 fmt = "%d"; 757 else if (synth_field_is_string(type)) 758 fmt = "%s"; 759 760 return fmt; 761 } 762 763 static enum print_line_t print_synth_event(struct trace_iterator *iter, 764 int flags, 765 struct trace_event *event) 766 { 767 struct trace_array *tr = iter->tr; 768 struct trace_seq *s = &iter->seq; 769 struct synth_trace_event *entry; 770 struct synth_event *se; 771 unsigned int i, n_u64; 772 char print_fmt[32]; 773 const char *fmt; 774 775 entry = (struct synth_trace_event *)iter->ent; 776 se = container_of(event, struct synth_event, call.event); 777 778 trace_seq_printf(s, "%s: ", se->name); 779 780 for (i = 0, n_u64 = 0; i < se->n_fields; i++) { 781 if (trace_seq_has_overflowed(s)) 782 goto end; 783 784 fmt = synth_field_fmt(se->fields[i]->type); 785 786 /* parameter types */ 787 if (tr->trace_flags & TRACE_ITER_VERBOSE) 788 trace_seq_printf(s, "%s ", fmt); 789 790 snprintf(print_fmt, sizeof(print_fmt), "%%s=%s%%s", fmt); 791 792 /* parameter values */ 793 if (se->fields[i]->is_string) { 794 trace_seq_printf(s, print_fmt, se->fields[i]->name, 795 (char *)&entry->fields[n_u64], 796 i == se->n_fields - 1 ? "" : " "); 797 n_u64 += STR_VAR_LEN_MAX / sizeof(u64); 798 } else { 799 trace_seq_printf(s, print_fmt, se->fields[i]->name, 800 entry->fields[n_u64], 801 i == se->n_fields - 1 ? "" : " "); 802 n_u64++; 803 } 804 } 805 end: 806 trace_seq_putc(s, '\n'); 807 808 return trace_handle_return(s); 809 } 810 811 static struct trace_event_functions synth_event_funcs = { 812 .trace = print_synth_event 813 }; 814 815 static notrace void trace_event_raw_event_synth(void *__data, 816 u64 *var_ref_vals, 817 unsigned int var_ref_idx) 818 { 819 struct trace_event_file *trace_file = __data; 820 struct synth_trace_event *entry; 821 struct trace_event_buffer fbuffer; 822 struct ring_buffer *buffer; 823 struct synth_event *event; 824 unsigned int i, n_u64; 825 int fields_size = 0; 826 827 event = trace_file->event_call->data; 828 829 if (trace_trigger_soft_disabled(trace_file)) 830 return; 831 832 fields_size = event->n_u64 * sizeof(u64); 833 834 /* 835 * Avoid ring buffer recursion detection, as this event 836 * is being performed within another event. 837 */ 838 buffer = trace_file->tr->trace_buffer.buffer; 839 ring_buffer_nest_start(buffer); 840 841 entry = trace_event_buffer_reserve(&fbuffer, trace_file, 842 sizeof(*entry) + fields_size); 843 if (!entry) 844 goto out; 845 846 for (i = 0, n_u64 = 0; i < event->n_fields; i++) { 847 if (event->fields[i]->is_string) { 848 char *str_val = (char *)(long)var_ref_vals[var_ref_idx + i]; 849 char *str_field = (char *)&entry->fields[n_u64]; 850 851 strscpy(str_field, str_val, STR_VAR_LEN_MAX); 852 n_u64 += STR_VAR_LEN_MAX / sizeof(u64); 853 } else { 854 entry->fields[n_u64] = var_ref_vals[var_ref_idx + i]; 855 n_u64++; 856 } 857 } 858 859 trace_event_buffer_commit(&fbuffer); 860 out: 861 ring_buffer_nest_end(buffer); 862 } 863 864 static void free_synth_event_print_fmt(struct trace_event_call *call) 865 { 866 if (call) { 867 kfree(call->print_fmt); 868 call->print_fmt = NULL; 869 } 870 } 871 872 static int __set_synth_event_print_fmt(struct synth_event *event, 873 char *buf, int len) 874 { 875 const char *fmt; 876 int pos = 0; 877 int i; 878 879 /* When len=0, we just calculate the needed length */ 880 #define LEN_OR_ZERO (len ? len - pos : 0) 881 882 pos += snprintf(buf + pos, LEN_OR_ZERO, "\""); 883 for (i = 0; i < event->n_fields; i++) { 884 fmt = synth_field_fmt(event->fields[i]->type); 885 pos += snprintf(buf + pos, LEN_OR_ZERO, "%s=%s%s", 886 event->fields[i]->name, fmt, 887 i == event->n_fields - 1 ? "" : ", "); 888 } 889 pos += snprintf(buf + pos, LEN_OR_ZERO, "\""); 890 891 for (i = 0; i < event->n_fields; i++) { 892 pos += snprintf(buf + pos, LEN_OR_ZERO, 893 ", REC->%s", event->fields[i]->name); 894 } 895 896 #undef LEN_OR_ZERO 897 898 /* return the length of print_fmt */ 899 return pos; 900 } 901 902 static int set_synth_event_print_fmt(struct trace_event_call *call) 903 { 904 struct synth_event *event = call->data; 905 char *print_fmt; 906 int len; 907 908 /* First: called with 0 length to calculate the needed length */ 909 len = __set_synth_event_print_fmt(event, NULL, 0); 910 911 print_fmt = kmalloc(len + 1, GFP_KERNEL); 912 if (!print_fmt) 913 return -ENOMEM; 914 915 /* Second: actually write the @print_fmt */ 916 __set_synth_event_print_fmt(event, print_fmt, len + 1); 917 call->print_fmt = print_fmt; 918 919 return 0; 920 } 921 922 static void free_synth_field(struct synth_field *field) 923 { 924 kfree(field->type); 925 kfree(field->name); 926 kfree(field); 927 } 928 929 static struct synth_field *parse_synth_field(int argc, const char **argv, 930 int *consumed) 931 { 932 struct synth_field *field; 933 const char *prefix = NULL, *field_type = argv[0], *field_name, *array; 934 int len, ret = 0; 935 936 if (field_type[0] == ';') 937 field_type++; 938 939 if (!strcmp(field_type, "unsigned")) { 940 if (argc < 3) 941 return ERR_PTR(-EINVAL); 942 prefix = "unsigned "; 943 field_type = argv[1]; 944 field_name = argv[2]; 945 *consumed = 3; 946 } else { 947 field_name = argv[1]; 948 *consumed = 2; 949 } 950 951 field = kzalloc(sizeof(*field), GFP_KERNEL); 952 if (!field) 953 return ERR_PTR(-ENOMEM); 954 955 len = strlen(field_name); 956 array = strchr(field_name, '['); 957 if (array) 958 len -= strlen(array); 959 else if (field_name[len - 1] == ';') 960 len--; 961 962 field->name = kmemdup_nul(field_name, len, GFP_KERNEL); 963 if (!field->name) { 964 ret = -ENOMEM; 965 goto free; 966 } 967 968 if (field_type[0] == ';') 969 field_type++; 970 len = strlen(field_type) + 1; 971 if (array) 972 len += strlen(array); 973 if (prefix) 974 len += strlen(prefix); 975 976 field->type = kzalloc(len, GFP_KERNEL); 977 if (!field->type) { 978 ret = -ENOMEM; 979 goto free; 980 } 981 if (prefix) 982 strcat(field->type, prefix); 983 strcat(field->type, field_type); 984 if (array) { 985 strcat(field->type, array); 986 if (field->type[len - 1] == ';') 987 field->type[len - 1] = '\0'; 988 } 989 990 field->size = synth_field_size(field->type); 991 if (!field->size) { 992 ret = -EINVAL; 993 goto free; 994 } 995 996 if (synth_field_is_string(field->type)) 997 field->is_string = true; 998 999 field->is_signed = synth_field_signed(field->type); 1000 1001 out: 1002 return field; 1003 free: 1004 free_synth_field(field); 1005 field = ERR_PTR(ret); 1006 goto out; 1007 } 1008 1009 static void free_synth_tracepoint(struct tracepoint *tp) 1010 { 1011 if (!tp) 1012 return; 1013 1014 kfree(tp->name); 1015 kfree(tp); 1016 } 1017 1018 static struct tracepoint *alloc_synth_tracepoint(char *name) 1019 { 1020 struct tracepoint *tp; 1021 1022 tp = kzalloc(sizeof(*tp), GFP_KERNEL); 1023 if (!tp) 1024 return ERR_PTR(-ENOMEM); 1025 1026 tp->name = kstrdup(name, GFP_KERNEL); 1027 if (!tp->name) { 1028 kfree(tp); 1029 return ERR_PTR(-ENOMEM); 1030 } 1031 1032 return tp; 1033 } 1034 1035 typedef void (*synth_probe_func_t) (void *__data, u64 *var_ref_vals, 1036 unsigned int var_ref_idx); 1037 1038 static inline void trace_synth(struct synth_event *event, u64 *var_ref_vals, 1039 unsigned int var_ref_idx) 1040 { 1041 struct tracepoint *tp = event->tp; 1042 1043 if (unlikely(atomic_read(&tp->key.enabled) > 0)) { 1044 struct tracepoint_func *probe_func_ptr; 1045 synth_probe_func_t probe_func; 1046 void *__data; 1047 1048 if (!(cpu_online(raw_smp_processor_id()))) 1049 return; 1050 1051 probe_func_ptr = rcu_dereference_sched((tp)->funcs); 1052 if (probe_func_ptr) { 1053 do { 1054 probe_func = probe_func_ptr->func; 1055 __data = probe_func_ptr->data; 1056 probe_func(__data, var_ref_vals, var_ref_idx); 1057 } while ((++probe_func_ptr)->func); 1058 } 1059 } 1060 } 1061 1062 static struct synth_event *find_synth_event(const char *name) 1063 { 1064 struct dyn_event *pos; 1065 struct synth_event *event; 1066 1067 for_each_dyn_event(pos) { 1068 if (!is_synth_event(pos)) 1069 continue; 1070 event = to_synth_event(pos); 1071 if (strcmp(event->name, name) == 0) 1072 return event; 1073 } 1074 1075 return NULL; 1076 } 1077 1078 static int register_synth_event(struct synth_event *event) 1079 { 1080 struct trace_event_call *call = &event->call; 1081 int ret = 0; 1082 1083 event->call.class = &event->class; 1084 event->class.system = kstrdup(SYNTH_SYSTEM, GFP_KERNEL); 1085 if (!event->class.system) { 1086 ret = -ENOMEM; 1087 goto out; 1088 } 1089 1090 event->tp = alloc_synth_tracepoint(event->name); 1091 if (IS_ERR(event->tp)) { 1092 ret = PTR_ERR(event->tp); 1093 event->tp = NULL; 1094 goto out; 1095 } 1096 1097 INIT_LIST_HEAD(&call->class->fields); 1098 call->event.funcs = &synth_event_funcs; 1099 call->class->define_fields = synth_event_define_fields; 1100 1101 ret = register_trace_event(&call->event); 1102 if (!ret) { 1103 ret = -ENODEV; 1104 goto out; 1105 } 1106 call->flags = TRACE_EVENT_FL_TRACEPOINT; 1107 call->class->reg = trace_event_reg; 1108 call->class->probe = trace_event_raw_event_synth; 1109 call->data = event; 1110 call->tp = event->tp; 1111 1112 ret = trace_add_event_call(call); 1113 if (ret) { 1114 pr_warn("Failed to register synthetic event: %s\n", 1115 trace_event_name(call)); 1116 goto err; 1117 } 1118 1119 ret = set_synth_event_print_fmt(call); 1120 if (ret < 0) { 1121 trace_remove_event_call(call); 1122 goto err; 1123 } 1124 out: 1125 return ret; 1126 err: 1127 unregister_trace_event(&call->event); 1128 goto out; 1129 } 1130 1131 static int unregister_synth_event(struct synth_event *event) 1132 { 1133 struct trace_event_call *call = &event->call; 1134 int ret; 1135 1136 ret = trace_remove_event_call(call); 1137 1138 return ret; 1139 } 1140 1141 static void free_synth_event(struct synth_event *event) 1142 { 1143 unsigned int i; 1144 1145 if (!event) 1146 return; 1147 1148 for (i = 0; i < event->n_fields; i++) 1149 free_synth_field(event->fields[i]); 1150 1151 kfree(event->fields); 1152 kfree(event->name); 1153 kfree(event->class.system); 1154 free_synth_tracepoint(event->tp); 1155 free_synth_event_print_fmt(&event->call); 1156 kfree(event); 1157 } 1158 1159 static struct synth_event *alloc_synth_event(const char *name, int n_fields, 1160 struct synth_field **fields) 1161 { 1162 struct synth_event *event; 1163 unsigned int i; 1164 1165 event = kzalloc(sizeof(*event), GFP_KERNEL); 1166 if (!event) { 1167 event = ERR_PTR(-ENOMEM); 1168 goto out; 1169 } 1170 1171 event->name = kstrdup(name, GFP_KERNEL); 1172 if (!event->name) { 1173 kfree(event); 1174 event = ERR_PTR(-ENOMEM); 1175 goto out; 1176 } 1177 1178 event->fields = kcalloc(n_fields, sizeof(*event->fields), GFP_KERNEL); 1179 if (!event->fields) { 1180 free_synth_event(event); 1181 event = ERR_PTR(-ENOMEM); 1182 goto out; 1183 } 1184 1185 dyn_event_init(&event->devent, &synth_event_ops); 1186 1187 for (i = 0; i < n_fields; i++) 1188 event->fields[i] = fields[i]; 1189 1190 event->n_fields = n_fields; 1191 out: 1192 return event; 1193 } 1194 1195 static void action_trace(struct hist_trigger_data *hist_data, 1196 struct tracing_map_elt *elt, void *rec, 1197 struct ring_buffer_event *rbe, void *key, 1198 struct action_data *data, u64 *var_ref_vals) 1199 { 1200 struct synth_event *event = data->synth_event; 1201 1202 trace_synth(event, var_ref_vals, data->var_ref_idx); 1203 } 1204 1205 struct hist_var_data { 1206 struct list_head list; 1207 struct hist_trigger_data *hist_data; 1208 }; 1209 1210 static int __create_synth_event(int argc, const char *name, const char **argv) 1211 { 1212 struct synth_field *field, *fields[SYNTH_FIELDS_MAX]; 1213 struct synth_event *event = NULL; 1214 int i, consumed = 0, n_fields = 0, ret = 0; 1215 1216 /* 1217 * Argument syntax: 1218 * - Add synthetic event: <event_name> field[;field] ... 1219 * - Remove synthetic event: !<event_name> field[;field] ... 1220 * where 'field' = type field_name 1221 */ 1222 1223 if (name[0] == '\0' || argc < 1) 1224 return -EINVAL; 1225 1226 mutex_lock(&event_mutex); 1227 1228 event = find_synth_event(name); 1229 if (event) { 1230 ret = -EEXIST; 1231 goto out; 1232 } 1233 1234 for (i = 0; i < argc - 1; i++) { 1235 if (strcmp(argv[i], ";") == 0) 1236 continue; 1237 if (n_fields == SYNTH_FIELDS_MAX) { 1238 ret = -EINVAL; 1239 goto err; 1240 } 1241 1242 field = parse_synth_field(argc - i, &argv[i], &consumed); 1243 if (IS_ERR(field)) { 1244 ret = PTR_ERR(field); 1245 goto err; 1246 } 1247 fields[n_fields++] = field; 1248 i += consumed - 1; 1249 } 1250 1251 if (i < argc && strcmp(argv[i], ";") != 0) { 1252 ret = -EINVAL; 1253 goto err; 1254 } 1255 1256 event = alloc_synth_event(name, n_fields, fields); 1257 if (IS_ERR(event)) { 1258 ret = PTR_ERR(event); 1259 event = NULL; 1260 goto err; 1261 } 1262 ret = register_synth_event(event); 1263 if (!ret) 1264 dyn_event_add(&event->devent); 1265 else 1266 free_synth_event(event); 1267 out: 1268 mutex_unlock(&event_mutex); 1269 1270 return ret; 1271 err: 1272 for (i = 0; i < n_fields; i++) 1273 free_synth_field(fields[i]); 1274 1275 goto out; 1276 } 1277 1278 static int create_or_delete_synth_event(int argc, char **argv) 1279 { 1280 const char *name = argv[0]; 1281 struct synth_event *event = NULL; 1282 int ret; 1283 1284 /* trace_run_command() ensures argc != 0 */ 1285 if (name[0] == '!') { 1286 mutex_lock(&event_mutex); 1287 event = find_synth_event(name + 1); 1288 if (event) { 1289 if (event->ref) 1290 ret = -EBUSY; 1291 else { 1292 ret = unregister_synth_event(event); 1293 if (!ret) { 1294 dyn_event_remove(&event->devent); 1295 free_synth_event(event); 1296 } 1297 } 1298 } else 1299 ret = -ENOENT; 1300 mutex_unlock(&event_mutex); 1301 return ret; 1302 } 1303 1304 ret = __create_synth_event(argc - 1, name, (const char **)argv + 1); 1305 return ret == -ECANCELED ? -EINVAL : ret; 1306 } 1307 1308 static int synth_event_create(int argc, const char **argv) 1309 { 1310 const char *name = argv[0]; 1311 int len; 1312 1313 if (name[0] != 's' || name[1] != ':') 1314 return -ECANCELED; 1315 name += 2; 1316 1317 /* This interface accepts group name prefix */ 1318 if (strchr(name, '/')) { 1319 len = str_has_prefix(name, SYNTH_SYSTEM "/"); 1320 if (len == 0) 1321 return -EINVAL; 1322 name += len; 1323 } 1324 return __create_synth_event(argc - 1, name, argv + 1); 1325 } 1326 1327 static int synth_event_release(struct dyn_event *ev) 1328 { 1329 struct synth_event *event = to_synth_event(ev); 1330 int ret; 1331 1332 if (event->ref) 1333 return -EBUSY; 1334 1335 ret = unregister_synth_event(event); 1336 if (ret) 1337 return ret; 1338 1339 dyn_event_remove(ev); 1340 free_synth_event(event); 1341 return 0; 1342 } 1343 1344 static int __synth_event_show(struct seq_file *m, struct synth_event *event) 1345 { 1346 struct synth_field *field; 1347 unsigned int i; 1348 1349 seq_printf(m, "%s\t", event->name); 1350 1351 for (i = 0; i < event->n_fields; i++) { 1352 field = event->fields[i]; 1353 1354 /* parameter values */ 1355 seq_printf(m, "%s %s%s", field->type, field->name, 1356 i == event->n_fields - 1 ? "" : "; "); 1357 } 1358 1359 seq_putc(m, '\n'); 1360 1361 return 0; 1362 } 1363 1364 static int synth_event_show(struct seq_file *m, struct dyn_event *ev) 1365 { 1366 struct synth_event *event = to_synth_event(ev); 1367 1368 seq_printf(m, "s:%s/", event->class.system); 1369 1370 return __synth_event_show(m, event); 1371 } 1372 1373 static int synth_events_seq_show(struct seq_file *m, void *v) 1374 { 1375 struct dyn_event *ev = v; 1376 1377 if (!is_synth_event(ev)) 1378 return 0; 1379 1380 return __synth_event_show(m, to_synth_event(ev)); 1381 } 1382 1383 static const struct seq_operations synth_events_seq_op = { 1384 .start = dyn_event_seq_start, 1385 .next = dyn_event_seq_next, 1386 .stop = dyn_event_seq_stop, 1387 .show = synth_events_seq_show, 1388 }; 1389 1390 static int synth_events_open(struct inode *inode, struct file *file) 1391 { 1392 int ret; 1393 1394 if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) { 1395 ret = dyn_events_release_all(&synth_event_ops); 1396 if (ret < 0) 1397 return ret; 1398 } 1399 1400 return seq_open(file, &synth_events_seq_op); 1401 } 1402 1403 static ssize_t synth_events_write(struct file *file, 1404 const char __user *buffer, 1405 size_t count, loff_t *ppos) 1406 { 1407 return trace_parse_run_command(file, buffer, count, ppos, 1408 create_or_delete_synth_event); 1409 } 1410 1411 static const struct file_operations synth_events_fops = { 1412 .open = synth_events_open, 1413 .write = synth_events_write, 1414 .read = seq_read, 1415 .llseek = seq_lseek, 1416 .release = seq_release, 1417 }; 1418 1419 static u64 hist_field_timestamp(struct hist_field *hist_field, 1420 struct tracing_map_elt *elt, 1421 struct ring_buffer_event *rbe, 1422 void *event) 1423 { 1424 struct hist_trigger_data *hist_data = hist_field->hist_data; 1425 struct trace_array *tr = hist_data->event_file->tr; 1426 1427 u64 ts = ring_buffer_event_time_stamp(rbe); 1428 1429 if (hist_data->attrs->ts_in_usecs && trace_clock_in_ns(tr)) 1430 ts = ns2usecs(ts); 1431 1432 return ts; 1433 } 1434 1435 static u64 hist_field_cpu(struct hist_field *hist_field, 1436 struct tracing_map_elt *elt, 1437 struct ring_buffer_event *rbe, 1438 void *event) 1439 { 1440 int cpu = smp_processor_id(); 1441 1442 return cpu; 1443 } 1444 1445 /** 1446 * check_field_for_var_ref - Check if a VAR_REF field references a variable 1447 * @hist_field: The VAR_REF field to check 1448 * @var_data: The hist trigger that owns the variable 1449 * @var_idx: The trigger variable identifier 1450 * 1451 * Check the given VAR_REF field to see whether or not it references 1452 * the given variable associated with the given trigger. 1453 * 1454 * Return: The VAR_REF field if it does reference the variable, NULL if not 1455 */ 1456 static struct hist_field * 1457 check_field_for_var_ref(struct hist_field *hist_field, 1458 struct hist_trigger_data *var_data, 1459 unsigned int var_idx) 1460 { 1461 WARN_ON(!(hist_field && hist_field->flags & HIST_FIELD_FL_VAR_REF)); 1462 1463 if (hist_field && hist_field->var.idx == var_idx && 1464 hist_field->var.hist_data == var_data) 1465 return hist_field; 1466 1467 return NULL; 1468 } 1469 1470 /** 1471 * find_var_ref - Check if a trigger has a reference to a trigger variable 1472 * @hist_data: The hist trigger that might have a reference to the variable 1473 * @var_data: The hist trigger that owns the variable 1474 * @var_idx: The trigger variable identifier 1475 * 1476 * Check the list of var_refs[] on the first hist trigger to see 1477 * whether any of them are references to the variable on the second 1478 * trigger. 1479 * 1480 * Return: The VAR_REF field referencing the variable if so, NULL if not 1481 */ 1482 static struct hist_field *find_var_ref(struct hist_trigger_data *hist_data, 1483 struct hist_trigger_data *var_data, 1484 unsigned int var_idx) 1485 { 1486 struct hist_field *hist_field; 1487 unsigned int i; 1488 1489 for (i = 0; i < hist_data->n_var_refs; i++) { 1490 hist_field = hist_data->var_refs[i]; 1491 if (check_field_for_var_ref(hist_field, var_data, var_idx)) 1492 return hist_field; 1493 } 1494 1495 return NULL; 1496 } 1497 1498 /** 1499 * find_any_var_ref - Check if there is a reference to a given trigger variable 1500 * @hist_data: The hist trigger 1501 * @var_idx: The trigger variable identifier 1502 * 1503 * Check to see whether the given variable is currently referenced by 1504 * any other trigger. 1505 * 1506 * The trigger the variable is defined on is explicitly excluded - the 1507 * assumption being that a self-reference doesn't prevent a trigger 1508 * from being removed. 1509 * 1510 * Return: The VAR_REF field referencing the variable if so, NULL if not 1511 */ 1512 static struct hist_field *find_any_var_ref(struct hist_trigger_data *hist_data, 1513 unsigned int var_idx) 1514 { 1515 struct trace_array *tr = hist_data->event_file->tr; 1516 struct hist_field *found = NULL; 1517 struct hist_var_data *var_data; 1518 1519 list_for_each_entry(var_data, &tr->hist_vars, list) { 1520 if (var_data->hist_data == hist_data) 1521 continue; 1522 found = find_var_ref(var_data->hist_data, hist_data, var_idx); 1523 if (found) 1524 break; 1525 } 1526 1527 return found; 1528 } 1529 1530 /** 1531 * check_var_refs - Check if there is a reference to any of trigger's variables 1532 * @hist_data: The hist trigger 1533 * 1534 * A trigger can define one or more variables. If any one of them is 1535 * currently referenced by any other trigger, this function will 1536 * determine that. 1537 1538 * Typically used to determine whether or not a trigger can be removed 1539 * - if there are any references to a trigger's variables, it cannot. 1540 * 1541 * Return: True if there is a reference to any of trigger's variables 1542 */ 1543 static bool check_var_refs(struct hist_trigger_data *hist_data) 1544 { 1545 struct hist_field *field; 1546 bool found = false; 1547 int i; 1548 1549 for_each_hist_field(i, hist_data) { 1550 field = hist_data->fields[i]; 1551 if (field && field->flags & HIST_FIELD_FL_VAR) { 1552 if (find_any_var_ref(hist_data, field->var.idx)) { 1553 found = true; 1554 break; 1555 } 1556 } 1557 } 1558 1559 return found; 1560 } 1561 1562 static struct hist_var_data *find_hist_vars(struct hist_trigger_data *hist_data) 1563 { 1564 struct trace_array *tr = hist_data->event_file->tr; 1565 struct hist_var_data *var_data, *found = NULL; 1566 1567 list_for_each_entry(var_data, &tr->hist_vars, list) { 1568 if (var_data->hist_data == hist_data) { 1569 found = var_data; 1570 break; 1571 } 1572 } 1573 1574 return found; 1575 } 1576 1577 static bool field_has_hist_vars(struct hist_field *hist_field, 1578 unsigned int level) 1579 { 1580 int i; 1581 1582 if (level > 3) 1583 return false; 1584 1585 if (!hist_field) 1586 return false; 1587 1588 if (hist_field->flags & HIST_FIELD_FL_VAR || 1589 hist_field->flags & HIST_FIELD_FL_VAR_REF) 1590 return true; 1591 1592 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) { 1593 struct hist_field *operand; 1594 1595 operand = hist_field->operands[i]; 1596 if (field_has_hist_vars(operand, level + 1)) 1597 return true; 1598 } 1599 1600 return false; 1601 } 1602 1603 static bool has_hist_vars(struct hist_trigger_data *hist_data) 1604 { 1605 struct hist_field *hist_field; 1606 int i; 1607 1608 for_each_hist_field(i, hist_data) { 1609 hist_field = hist_data->fields[i]; 1610 if (field_has_hist_vars(hist_field, 0)) 1611 return true; 1612 } 1613 1614 return false; 1615 } 1616 1617 static int save_hist_vars(struct hist_trigger_data *hist_data) 1618 { 1619 struct trace_array *tr = hist_data->event_file->tr; 1620 struct hist_var_data *var_data; 1621 1622 var_data = find_hist_vars(hist_data); 1623 if (var_data) 1624 return 0; 1625 1626 if (trace_array_get(tr) < 0) 1627 return -ENODEV; 1628 1629 var_data = kzalloc(sizeof(*var_data), GFP_KERNEL); 1630 if (!var_data) { 1631 trace_array_put(tr); 1632 return -ENOMEM; 1633 } 1634 1635 var_data->hist_data = hist_data; 1636 list_add(&var_data->list, &tr->hist_vars); 1637 1638 return 0; 1639 } 1640 1641 static void remove_hist_vars(struct hist_trigger_data *hist_data) 1642 { 1643 struct trace_array *tr = hist_data->event_file->tr; 1644 struct hist_var_data *var_data; 1645 1646 var_data = find_hist_vars(hist_data); 1647 if (!var_data) 1648 return; 1649 1650 if (WARN_ON(check_var_refs(hist_data))) 1651 return; 1652 1653 list_del(&var_data->list); 1654 1655 kfree(var_data); 1656 1657 trace_array_put(tr); 1658 } 1659 1660 static struct hist_field *find_var_field(struct hist_trigger_data *hist_data, 1661 const char *var_name) 1662 { 1663 struct hist_field *hist_field, *found = NULL; 1664 int i; 1665 1666 for_each_hist_field(i, hist_data) { 1667 hist_field = hist_data->fields[i]; 1668 if (hist_field && hist_field->flags & HIST_FIELD_FL_VAR && 1669 strcmp(hist_field->var.name, var_name) == 0) { 1670 found = hist_field; 1671 break; 1672 } 1673 } 1674 1675 return found; 1676 } 1677 1678 static struct hist_field *find_var(struct hist_trigger_data *hist_data, 1679 struct trace_event_file *file, 1680 const char *var_name) 1681 { 1682 struct hist_trigger_data *test_data; 1683 struct event_trigger_data *test; 1684 struct hist_field *hist_field; 1685 1686 hist_field = find_var_field(hist_data, var_name); 1687 if (hist_field) 1688 return hist_field; 1689 1690 list_for_each_entry_rcu(test, &file->triggers, list) { 1691 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 1692 test_data = test->private_data; 1693 hist_field = find_var_field(test_data, var_name); 1694 if (hist_field) 1695 return hist_field; 1696 } 1697 } 1698 1699 return NULL; 1700 } 1701 1702 static struct trace_event_file *find_var_file(struct trace_array *tr, 1703 char *system, 1704 char *event_name, 1705 char *var_name) 1706 { 1707 struct hist_trigger_data *var_hist_data; 1708 struct hist_var_data *var_data; 1709 struct trace_event_file *file, *found = NULL; 1710 1711 if (system) 1712 return find_event_file(tr, system, event_name); 1713 1714 list_for_each_entry(var_data, &tr->hist_vars, list) { 1715 var_hist_data = var_data->hist_data; 1716 file = var_hist_data->event_file; 1717 if (file == found) 1718 continue; 1719 1720 if (find_var_field(var_hist_data, var_name)) { 1721 if (found) { 1722 hist_err_event("Variable name not unique, need to use fully qualified name (subsys.event.var) for variable: ", system, event_name, var_name); 1723 return NULL; 1724 } 1725 1726 found = file; 1727 } 1728 } 1729 1730 return found; 1731 } 1732 1733 static struct hist_field *find_file_var(struct trace_event_file *file, 1734 const char *var_name) 1735 { 1736 struct hist_trigger_data *test_data; 1737 struct event_trigger_data *test; 1738 struct hist_field *hist_field; 1739 1740 list_for_each_entry_rcu(test, &file->triggers, list) { 1741 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 1742 test_data = test->private_data; 1743 hist_field = find_var_field(test_data, var_name); 1744 if (hist_field) 1745 return hist_field; 1746 } 1747 } 1748 1749 return NULL; 1750 } 1751 1752 static struct hist_field * 1753 find_match_var(struct hist_trigger_data *hist_data, char *var_name) 1754 { 1755 struct trace_array *tr = hist_data->event_file->tr; 1756 struct hist_field *hist_field, *found = NULL; 1757 struct trace_event_file *file; 1758 unsigned int i; 1759 1760 for (i = 0; i < hist_data->n_actions; i++) { 1761 struct action_data *data = hist_data->actions[i]; 1762 1763 if (data->handler == HANDLER_ONMATCH) { 1764 char *system = data->match_data.event_system; 1765 char *event_name = data->match_data.event; 1766 1767 file = find_var_file(tr, system, event_name, var_name); 1768 if (!file) 1769 continue; 1770 hist_field = find_file_var(file, var_name); 1771 if (hist_field) { 1772 if (found) { 1773 hist_err_event("Variable name not unique, need to use fully qualified name (subsys.event.var) for variable: ", system, event_name, var_name); 1774 return ERR_PTR(-EINVAL); 1775 } 1776 1777 found = hist_field; 1778 } 1779 } 1780 } 1781 return found; 1782 } 1783 1784 static struct hist_field *find_event_var(struct hist_trigger_data *hist_data, 1785 char *system, 1786 char *event_name, 1787 char *var_name) 1788 { 1789 struct trace_array *tr = hist_data->event_file->tr; 1790 struct hist_field *hist_field = NULL; 1791 struct trace_event_file *file; 1792 1793 if (!system || !event_name) { 1794 hist_field = find_match_var(hist_data, var_name); 1795 if (IS_ERR(hist_field)) 1796 return NULL; 1797 if (hist_field) 1798 return hist_field; 1799 } 1800 1801 file = find_var_file(tr, system, event_name, var_name); 1802 if (!file) 1803 return NULL; 1804 1805 hist_field = find_file_var(file, var_name); 1806 1807 return hist_field; 1808 } 1809 1810 static u64 hist_field_var_ref(struct hist_field *hist_field, 1811 struct tracing_map_elt *elt, 1812 struct ring_buffer_event *rbe, 1813 void *event) 1814 { 1815 struct hist_elt_data *elt_data; 1816 u64 var_val = 0; 1817 1818 elt_data = elt->private_data; 1819 var_val = elt_data->var_ref_vals[hist_field->var_ref_idx]; 1820 1821 return var_val; 1822 } 1823 1824 static bool resolve_var_refs(struct hist_trigger_data *hist_data, void *key, 1825 u64 *var_ref_vals, bool self) 1826 { 1827 struct hist_trigger_data *var_data; 1828 struct tracing_map_elt *var_elt; 1829 struct hist_field *hist_field; 1830 unsigned int i, var_idx; 1831 bool resolved = true; 1832 u64 var_val = 0; 1833 1834 for (i = 0; i < hist_data->n_var_refs; i++) { 1835 hist_field = hist_data->var_refs[i]; 1836 var_idx = hist_field->var.idx; 1837 var_data = hist_field->var.hist_data; 1838 1839 if (var_data == NULL) { 1840 resolved = false; 1841 break; 1842 } 1843 1844 if ((self && var_data != hist_data) || 1845 (!self && var_data == hist_data)) 1846 continue; 1847 1848 var_elt = tracing_map_lookup(var_data->map, key); 1849 if (!var_elt) { 1850 resolved = false; 1851 break; 1852 } 1853 1854 if (!tracing_map_var_set(var_elt, var_idx)) { 1855 resolved = false; 1856 break; 1857 } 1858 1859 if (self || !hist_field->read_once) 1860 var_val = tracing_map_read_var(var_elt, var_idx); 1861 else 1862 var_val = tracing_map_read_var_once(var_elt, var_idx); 1863 1864 var_ref_vals[i] = var_val; 1865 } 1866 1867 return resolved; 1868 } 1869 1870 static const char *hist_field_name(struct hist_field *field, 1871 unsigned int level) 1872 { 1873 const char *field_name = ""; 1874 1875 if (level > 1) 1876 return field_name; 1877 1878 if (field->field) 1879 field_name = field->field->name; 1880 else if (field->flags & HIST_FIELD_FL_LOG2 || 1881 field->flags & HIST_FIELD_FL_ALIAS) 1882 field_name = hist_field_name(field->operands[0], ++level); 1883 else if (field->flags & HIST_FIELD_FL_CPU) 1884 field_name = "cpu"; 1885 else if (field->flags & HIST_FIELD_FL_EXPR || 1886 field->flags & HIST_FIELD_FL_VAR_REF) { 1887 if (field->system) { 1888 static char full_name[MAX_FILTER_STR_VAL]; 1889 1890 strcat(full_name, field->system); 1891 strcat(full_name, "."); 1892 strcat(full_name, field->event_name); 1893 strcat(full_name, "."); 1894 strcat(full_name, field->name); 1895 field_name = full_name; 1896 } else 1897 field_name = field->name; 1898 } else if (field->flags & HIST_FIELD_FL_TIMESTAMP) 1899 field_name = "common_timestamp"; 1900 1901 if (field_name == NULL) 1902 field_name = ""; 1903 1904 return field_name; 1905 } 1906 1907 static hist_field_fn_t select_value_fn(int field_size, int field_is_signed) 1908 { 1909 hist_field_fn_t fn = NULL; 1910 1911 switch (field_size) { 1912 case 8: 1913 if (field_is_signed) 1914 fn = hist_field_s64; 1915 else 1916 fn = hist_field_u64; 1917 break; 1918 case 4: 1919 if (field_is_signed) 1920 fn = hist_field_s32; 1921 else 1922 fn = hist_field_u32; 1923 break; 1924 case 2: 1925 if (field_is_signed) 1926 fn = hist_field_s16; 1927 else 1928 fn = hist_field_u16; 1929 break; 1930 case 1: 1931 if (field_is_signed) 1932 fn = hist_field_s8; 1933 else 1934 fn = hist_field_u8; 1935 break; 1936 } 1937 1938 return fn; 1939 } 1940 1941 static int parse_map_size(char *str) 1942 { 1943 unsigned long size, map_bits; 1944 int ret; 1945 1946 strsep(&str, "="); 1947 if (!str) { 1948 ret = -EINVAL; 1949 goto out; 1950 } 1951 1952 ret = kstrtoul(str, 0, &size); 1953 if (ret) 1954 goto out; 1955 1956 map_bits = ilog2(roundup_pow_of_two(size)); 1957 if (map_bits < TRACING_MAP_BITS_MIN || 1958 map_bits > TRACING_MAP_BITS_MAX) 1959 ret = -EINVAL; 1960 else 1961 ret = map_bits; 1962 out: 1963 return ret; 1964 } 1965 1966 static void destroy_hist_trigger_attrs(struct hist_trigger_attrs *attrs) 1967 { 1968 unsigned int i; 1969 1970 if (!attrs) 1971 return; 1972 1973 for (i = 0; i < attrs->n_assignments; i++) 1974 kfree(attrs->assignment_str[i]); 1975 1976 for (i = 0; i < attrs->n_actions; i++) 1977 kfree(attrs->action_str[i]); 1978 1979 kfree(attrs->name); 1980 kfree(attrs->sort_key_str); 1981 kfree(attrs->keys_str); 1982 kfree(attrs->vals_str); 1983 kfree(attrs->clock); 1984 kfree(attrs); 1985 } 1986 1987 static int parse_action(char *str, struct hist_trigger_attrs *attrs) 1988 { 1989 int ret = -EINVAL; 1990 1991 if (attrs->n_actions >= HIST_ACTIONS_MAX) 1992 return ret; 1993 1994 if ((str_has_prefix(str, "onmatch(")) || 1995 (str_has_prefix(str, "onmax(")) || 1996 (str_has_prefix(str, "onchange("))) { 1997 attrs->action_str[attrs->n_actions] = kstrdup(str, GFP_KERNEL); 1998 if (!attrs->action_str[attrs->n_actions]) { 1999 ret = -ENOMEM; 2000 return ret; 2001 } 2002 attrs->n_actions++; 2003 ret = 0; 2004 } 2005 2006 return ret; 2007 } 2008 2009 static int parse_assignment(char *str, struct hist_trigger_attrs *attrs) 2010 { 2011 int ret = 0; 2012 2013 if ((str_has_prefix(str, "key=")) || 2014 (str_has_prefix(str, "keys="))) { 2015 attrs->keys_str = kstrdup(str, GFP_KERNEL); 2016 if (!attrs->keys_str) { 2017 ret = -ENOMEM; 2018 goto out; 2019 } 2020 } else if ((str_has_prefix(str, "val=")) || 2021 (str_has_prefix(str, "vals=")) || 2022 (str_has_prefix(str, "values="))) { 2023 attrs->vals_str = kstrdup(str, GFP_KERNEL); 2024 if (!attrs->vals_str) { 2025 ret = -ENOMEM; 2026 goto out; 2027 } 2028 } else if (str_has_prefix(str, "sort=")) { 2029 attrs->sort_key_str = kstrdup(str, GFP_KERNEL); 2030 if (!attrs->sort_key_str) { 2031 ret = -ENOMEM; 2032 goto out; 2033 } 2034 } else if (str_has_prefix(str, "name=")) { 2035 attrs->name = kstrdup(str, GFP_KERNEL); 2036 if (!attrs->name) { 2037 ret = -ENOMEM; 2038 goto out; 2039 } 2040 } else if (str_has_prefix(str, "clock=")) { 2041 strsep(&str, "="); 2042 if (!str) { 2043 ret = -EINVAL; 2044 goto out; 2045 } 2046 2047 str = strstrip(str); 2048 attrs->clock = kstrdup(str, GFP_KERNEL); 2049 if (!attrs->clock) { 2050 ret = -ENOMEM; 2051 goto out; 2052 } 2053 } else if (str_has_prefix(str, "size=")) { 2054 int map_bits = parse_map_size(str); 2055 2056 if (map_bits < 0) { 2057 ret = map_bits; 2058 goto out; 2059 } 2060 attrs->map_bits = map_bits; 2061 } else { 2062 char *assignment; 2063 2064 if (attrs->n_assignments == TRACING_MAP_VARS_MAX) { 2065 hist_err("Too many variables defined: ", str); 2066 ret = -EINVAL; 2067 goto out; 2068 } 2069 2070 assignment = kstrdup(str, GFP_KERNEL); 2071 if (!assignment) { 2072 ret = -ENOMEM; 2073 goto out; 2074 } 2075 2076 attrs->assignment_str[attrs->n_assignments++] = assignment; 2077 } 2078 out: 2079 return ret; 2080 } 2081 2082 static struct hist_trigger_attrs *parse_hist_trigger_attrs(char *trigger_str) 2083 { 2084 struct hist_trigger_attrs *attrs; 2085 int ret = 0; 2086 2087 attrs = kzalloc(sizeof(*attrs), GFP_KERNEL); 2088 if (!attrs) 2089 return ERR_PTR(-ENOMEM); 2090 2091 while (trigger_str) { 2092 char *str = strsep(&trigger_str, ":"); 2093 2094 if (strchr(str, '=')) { 2095 ret = parse_assignment(str, attrs); 2096 if (ret) 2097 goto free; 2098 } else if (strcmp(str, "pause") == 0) 2099 attrs->pause = true; 2100 else if ((strcmp(str, "cont") == 0) || 2101 (strcmp(str, "continue") == 0)) 2102 attrs->cont = true; 2103 else if (strcmp(str, "clear") == 0) 2104 attrs->clear = true; 2105 else { 2106 ret = parse_action(str, attrs); 2107 if (ret) 2108 goto free; 2109 } 2110 } 2111 2112 if (!attrs->keys_str) { 2113 ret = -EINVAL; 2114 goto free; 2115 } 2116 2117 if (!attrs->clock) { 2118 attrs->clock = kstrdup("global", GFP_KERNEL); 2119 if (!attrs->clock) { 2120 ret = -ENOMEM; 2121 goto free; 2122 } 2123 } 2124 2125 return attrs; 2126 free: 2127 destroy_hist_trigger_attrs(attrs); 2128 2129 return ERR_PTR(ret); 2130 } 2131 2132 static inline void save_comm(char *comm, struct task_struct *task) 2133 { 2134 if (!task->pid) { 2135 strcpy(comm, "<idle>"); 2136 return; 2137 } 2138 2139 if (WARN_ON_ONCE(task->pid < 0)) { 2140 strcpy(comm, "<XXX>"); 2141 return; 2142 } 2143 2144 strncpy(comm, task->comm, TASK_COMM_LEN); 2145 } 2146 2147 static void hist_elt_data_free(struct hist_elt_data *elt_data) 2148 { 2149 unsigned int i; 2150 2151 for (i = 0; i < SYNTH_FIELDS_MAX; i++) 2152 kfree(elt_data->field_var_str[i]); 2153 2154 kfree(elt_data->comm); 2155 kfree(elt_data); 2156 } 2157 2158 static void hist_trigger_elt_data_free(struct tracing_map_elt *elt) 2159 { 2160 struct hist_elt_data *elt_data = elt->private_data; 2161 2162 hist_elt_data_free(elt_data); 2163 } 2164 2165 static int hist_trigger_elt_data_alloc(struct tracing_map_elt *elt) 2166 { 2167 struct hist_trigger_data *hist_data = elt->map->private_data; 2168 unsigned int size = TASK_COMM_LEN; 2169 struct hist_elt_data *elt_data; 2170 struct hist_field *key_field; 2171 unsigned int i, n_str; 2172 2173 elt_data = kzalloc(sizeof(*elt_data), GFP_KERNEL); 2174 if (!elt_data) 2175 return -ENOMEM; 2176 2177 for_each_hist_key_field(i, hist_data) { 2178 key_field = hist_data->fields[i]; 2179 2180 if (key_field->flags & HIST_FIELD_FL_EXECNAME) { 2181 elt_data->comm = kzalloc(size, GFP_KERNEL); 2182 if (!elt_data->comm) { 2183 kfree(elt_data); 2184 return -ENOMEM; 2185 } 2186 break; 2187 } 2188 } 2189 2190 n_str = hist_data->n_field_var_str + hist_data->n_save_var_str; 2191 2192 size = STR_VAR_LEN_MAX; 2193 2194 for (i = 0; i < n_str; i++) { 2195 elt_data->field_var_str[i] = kzalloc(size, GFP_KERNEL); 2196 if (!elt_data->field_var_str[i]) { 2197 hist_elt_data_free(elt_data); 2198 return -ENOMEM; 2199 } 2200 } 2201 2202 elt->private_data = elt_data; 2203 2204 return 0; 2205 } 2206 2207 static void hist_trigger_elt_data_init(struct tracing_map_elt *elt) 2208 { 2209 struct hist_elt_data *elt_data = elt->private_data; 2210 2211 if (elt_data->comm) 2212 save_comm(elt_data->comm, current); 2213 } 2214 2215 static const struct tracing_map_ops hist_trigger_elt_data_ops = { 2216 .elt_alloc = hist_trigger_elt_data_alloc, 2217 .elt_free = hist_trigger_elt_data_free, 2218 .elt_init = hist_trigger_elt_data_init, 2219 }; 2220 2221 static const char *get_hist_field_flags(struct hist_field *hist_field) 2222 { 2223 const char *flags_str = NULL; 2224 2225 if (hist_field->flags & HIST_FIELD_FL_HEX) 2226 flags_str = "hex"; 2227 else if (hist_field->flags & HIST_FIELD_FL_SYM) 2228 flags_str = "sym"; 2229 else if (hist_field->flags & HIST_FIELD_FL_SYM_OFFSET) 2230 flags_str = "sym-offset"; 2231 else if (hist_field->flags & HIST_FIELD_FL_EXECNAME) 2232 flags_str = "execname"; 2233 else if (hist_field->flags & HIST_FIELD_FL_SYSCALL) 2234 flags_str = "syscall"; 2235 else if (hist_field->flags & HIST_FIELD_FL_LOG2) 2236 flags_str = "log2"; 2237 else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS) 2238 flags_str = "usecs"; 2239 2240 return flags_str; 2241 } 2242 2243 static void expr_field_str(struct hist_field *field, char *expr) 2244 { 2245 if (field->flags & HIST_FIELD_FL_VAR_REF) 2246 strcat(expr, "$"); 2247 2248 strcat(expr, hist_field_name(field, 0)); 2249 2250 if (field->flags && !(field->flags & HIST_FIELD_FL_VAR_REF)) { 2251 const char *flags_str = get_hist_field_flags(field); 2252 2253 if (flags_str) { 2254 strcat(expr, "."); 2255 strcat(expr, flags_str); 2256 } 2257 } 2258 } 2259 2260 static char *expr_str(struct hist_field *field, unsigned int level) 2261 { 2262 char *expr; 2263 2264 if (level > 1) 2265 return NULL; 2266 2267 expr = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 2268 if (!expr) 2269 return NULL; 2270 2271 if (!field->operands[0]) { 2272 expr_field_str(field, expr); 2273 return expr; 2274 } 2275 2276 if (field->operator == FIELD_OP_UNARY_MINUS) { 2277 char *subexpr; 2278 2279 strcat(expr, "-("); 2280 subexpr = expr_str(field->operands[0], ++level); 2281 if (!subexpr) { 2282 kfree(expr); 2283 return NULL; 2284 } 2285 strcat(expr, subexpr); 2286 strcat(expr, ")"); 2287 2288 kfree(subexpr); 2289 2290 return expr; 2291 } 2292 2293 expr_field_str(field->operands[0], expr); 2294 2295 switch (field->operator) { 2296 case FIELD_OP_MINUS: 2297 strcat(expr, "-"); 2298 break; 2299 case FIELD_OP_PLUS: 2300 strcat(expr, "+"); 2301 break; 2302 default: 2303 kfree(expr); 2304 return NULL; 2305 } 2306 2307 expr_field_str(field->operands[1], expr); 2308 2309 return expr; 2310 } 2311 2312 static int contains_operator(char *str) 2313 { 2314 enum field_op_id field_op = FIELD_OP_NONE; 2315 char *op; 2316 2317 op = strpbrk(str, "+-"); 2318 if (!op) 2319 return FIELD_OP_NONE; 2320 2321 switch (*op) { 2322 case '-': 2323 if (*str == '-') 2324 field_op = FIELD_OP_UNARY_MINUS; 2325 else 2326 field_op = FIELD_OP_MINUS; 2327 break; 2328 case '+': 2329 field_op = FIELD_OP_PLUS; 2330 break; 2331 default: 2332 break; 2333 } 2334 2335 return field_op; 2336 } 2337 2338 static void __destroy_hist_field(struct hist_field *hist_field) 2339 { 2340 kfree(hist_field->var.name); 2341 kfree(hist_field->name); 2342 kfree(hist_field->type); 2343 2344 kfree(hist_field); 2345 } 2346 2347 static void destroy_hist_field(struct hist_field *hist_field, 2348 unsigned int level) 2349 { 2350 unsigned int i; 2351 2352 if (level > 3) 2353 return; 2354 2355 if (!hist_field) 2356 return; 2357 2358 if (hist_field->flags & HIST_FIELD_FL_VAR_REF) 2359 return; /* var refs will be destroyed separately */ 2360 2361 for (i = 0; i < HIST_FIELD_OPERANDS_MAX; i++) 2362 destroy_hist_field(hist_field->operands[i], level + 1); 2363 2364 __destroy_hist_field(hist_field); 2365 } 2366 2367 static struct hist_field *create_hist_field(struct hist_trigger_data *hist_data, 2368 struct ftrace_event_field *field, 2369 unsigned long flags, 2370 char *var_name) 2371 { 2372 struct hist_field *hist_field; 2373 2374 if (field && is_function_field(field)) 2375 return NULL; 2376 2377 hist_field = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 2378 if (!hist_field) 2379 return NULL; 2380 2381 hist_field->hist_data = hist_data; 2382 2383 if (flags & HIST_FIELD_FL_EXPR || flags & HIST_FIELD_FL_ALIAS) 2384 goto out; /* caller will populate */ 2385 2386 if (flags & HIST_FIELD_FL_VAR_REF) { 2387 hist_field->fn = hist_field_var_ref; 2388 goto out; 2389 } 2390 2391 if (flags & HIST_FIELD_FL_HITCOUNT) { 2392 hist_field->fn = hist_field_counter; 2393 hist_field->size = sizeof(u64); 2394 hist_field->type = kstrdup("u64", GFP_KERNEL); 2395 if (!hist_field->type) 2396 goto free; 2397 goto out; 2398 } 2399 2400 if (flags & HIST_FIELD_FL_STACKTRACE) { 2401 hist_field->fn = hist_field_none; 2402 goto out; 2403 } 2404 2405 if (flags & HIST_FIELD_FL_LOG2) { 2406 unsigned long fl = flags & ~HIST_FIELD_FL_LOG2; 2407 hist_field->fn = hist_field_log2; 2408 hist_field->operands[0] = create_hist_field(hist_data, field, fl, NULL); 2409 hist_field->size = hist_field->operands[0]->size; 2410 hist_field->type = kstrdup(hist_field->operands[0]->type, GFP_KERNEL); 2411 if (!hist_field->type) 2412 goto free; 2413 goto out; 2414 } 2415 2416 if (flags & HIST_FIELD_FL_TIMESTAMP) { 2417 hist_field->fn = hist_field_timestamp; 2418 hist_field->size = sizeof(u64); 2419 hist_field->type = kstrdup("u64", GFP_KERNEL); 2420 if (!hist_field->type) 2421 goto free; 2422 goto out; 2423 } 2424 2425 if (flags & HIST_FIELD_FL_CPU) { 2426 hist_field->fn = hist_field_cpu; 2427 hist_field->size = sizeof(int); 2428 hist_field->type = kstrdup("unsigned int", GFP_KERNEL); 2429 if (!hist_field->type) 2430 goto free; 2431 goto out; 2432 } 2433 2434 if (WARN_ON_ONCE(!field)) 2435 goto out; 2436 2437 if (is_string_field(field)) { 2438 flags |= HIST_FIELD_FL_STRING; 2439 2440 hist_field->size = MAX_FILTER_STR_VAL; 2441 hist_field->type = kstrdup(field->type, GFP_KERNEL); 2442 if (!hist_field->type) 2443 goto free; 2444 2445 if (field->filter_type == FILTER_STATIC_STRING) 2446 hist_field->fn = hist_field_string; 2447 else if (field->filter_type == FILTER_DYN_STRING) 2448 hist_field->fn = hist_field_dynstring; 2449 else 2450 hist_field->fn = hist_field_pstring; 2451 } else { 2452 hist_field->size = field->size; 2453 hist_field->is_signed = field->is_signed; 2454 hist_field->type = kstrdup(field->type, GFP_KERNEL); 2455 if (!hist_field->type) 2456 goto free; 2457 2458 hist_field->fn = select_value_fn(field->size, 2459 field->is_signed); 2460 if (!hist_field->fn) { 2461 destroy_hist_field(hist_field, 0); 2462 return NULL; 2463 } 2464 } 2465 out: 2466 hist_field->field = field; 2467 hist_field->flags = flags; 2468 2469 if (var_name) { 2470 hist_field->var.name = kstrdup(var_name, GFP_KERNEL); 2471 if (!hist_field->var.name) 2472 goto free; 2473 } 2474 2475 return hist_field; 2476 free: 2477 destroy_hist_field(hist_field, 0); 2478 return NULL; 2479 } 2480 2481 static void destroy_hist_fields(struct hist_trigger_data *hist_data) 2482 { 2483 unsigned int i; 2484 2485 for (i = 0; i < HIST_FIELDS_MAX; i++) { 2486 if (hist_data->fields[i]) { 2487 destroy_hist_field(hist_data->fields[i], 0); 2488 hist_data->fields[i] = NULL; 2489 } 2490 } 2491 2492 for (i = 0; i < hist_data->n_var_refs; i++) { 2493 WARN_ON(!(hist_data->var_refs[i]->flags & HIST_FIELD_FL_VAR_REF)); 2494 __destroy_hist_field(hist_data->var_refs[i]); 2495 hist_data->var_refs[i] = NULL; 2496 } 2497 } 2498 2499 static int init_var_ref(struct hist_field *ref_field, 2500 struct hist_field *var_field, 2501 char *system, char *event_name) 2502 { 2503 int err = 0; 2504 2505 ref_field->var.idx = var_field->var.idx; 2506 ref_field->var.hist_data = var_field->hist_data; 2507 ref_field->size = var_field->size; 2508 ref_field->is_signed = var_field->is_signed; 2509 ref_field->flags |= var_field->flags & 2510 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2511 2512 if (system) { 2513 ref_field->system = kstrdup(system, GFP_KERNEL); 2514 if (!ref_field->system) 2515 return -ENOMEM; 2516 } 2517 2518 if (event_name) { 2519 ref_field->event_name = kstrdup(event_name, GFP_KERNEL); 2520 if (!ref_field->event_name) { 2521 err = -ENOMEM; 2522 goto free; 2523 } 2524 } 2525 2526 if (var_field->var.name) { 2527 ref_field->name = kstrdup(var_field->var.name, GFP_KERNEL); 2528 if (!ref_field->name) { 2529 err = -ENOMEM; 2530 goto free; 2531 } 2532 } else if (var_field->name) { 2533 ref_field->name = kstrdup(var_field->name, GFP_KERNEL); 2534 if (!ref_field->name) { 2535 err = -ENOMEM; 2536 goto free; 2537 } 2538 } 2539 2540 ref_field->type = kstrdup(var_field->type, GFP_KERNEL); 2541 if (!ref_field->type) { 2542 err = -ENOMEM; 2543 goto free; 2544 } 2545 out: 2546 return err; 2547 free: 2548 kfree(ref_field->system); 2549 kfree(ref_field->event_name); 2550 kfree(ref_field->name); 2551 2552 goto out; 2553 } 2554 2555 /** 2556 * create_var_ref - Create a variable reference and attach it to trigger 2557 * @hist_data: The trigger that will be referencing the variable 2558 * @var_field: The VAR field to create a reference to 2559 * @system: The optional system string 2560 * @event_name: The optional event_name string 2561 * 2562 * Given a variable hist_field, create a VAR_REF hist_field that 2563 * represents a reference to it. 2564 * 2565 * This function also adds the reference to the trigger that 2566 * now references the variable. 2567 * 2568 * Return: The VAR_REF field if successful, NULL if not 2569 */ 2570 static struct hist_field *create_var_ref(struct hist_trigger_data *hist_data, 2571 struct hist_field *var_field, 2572 char *system, char *event_name) 2573 { 2574 unsigned long flags = HIST_FIELD_FL_VAR_REF; 2575 struct hist_field *ref_field; 2576 2577 ref_field = create_hist_field(var_field->hist_data, NULL, flags, NULL); 2578 if (ref_field) { 2579 if (init_var_ref(ref_field, var_field, system, event_name)) { 2580 destroy_hist_field(ref_field, 0); 2581 return NULL; 2582 } 2583 2584 hist_data->var_refs[hist_data->n_var_refs] = ref_field; 2585 ref_field->var_ref_idx = hist_data->n_var_refs++; 2586 } 2587 2588 return ref_field; 2589 } 2590 2591 static bool is_var_ref(char *var_name) 2592 { 2593 if (!var_name || strlen(var_name) < 2 || var_name[0] != '$') 2594 return false; 2595 2596 return true; 2597 } 2598 2599 static char *field_name_from_var(struct hist_trigger_data *hist_data, 2600 char *var_name) 2601 { 2602 char *name, *field; 2603 unsigned int i; 2604 2605 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 2606 name = hist_data->attrs->var_defs.name[i]; 2607 2608 if (strcmp(var_name, name) == 0) { 2609 field = hist_data->attrs->var_defs.expr[i]; 2610 if (contains_operator(field) || is_var_ref(field)) 2611 continue; 2612 return field; 2613 } 2614 } 2615 2616 return NULL; 2617 } 2618 2619 static char *local_field_var_ref(struct hist_trigger_data *hist_data, 2620 char *system, char *event_name, 2621 char *var_name) 2622 { 2623 struct trace_event_call *call; 2624 2625 if (system && event_name) { 2626 call = hist_data->event_file->event_call; 2627 2628 if (strcmp(system, call->class->system) != 0) 2629 return NULL; 2630 2631 if (strcmp(event_name, trace_event_name(call)) != 0) 2632 return NULL; 2633 } 2634 2635 if (!!system != !!event_name) 2636 return NULL; 2637 2638 if (!is_var_ref(var_name)) 2639 return NULL; 2640 2641 var_name++; 2642 2643 return field_name_from_var(hist_data, var_name); 2644 } 2645 2646 static struct hist_field *parse_var_ref(struct hist_trigger_data *hist_data, 2647 char *system, char *event_name, 2648 char *var_name) 2649 { 2650 struct hist_field *var_field = NULL, *ref_field = NULL; 2651 2652 if (!is_var_ref(var_name)) 2653 return NULL; 2654 2655 var_name++; 2656 2657 var_field = find_event_var(hist_data, system, event_name, var_name); 2658 if (var_field) 2659 ref_field = create_var_ref(hist_data, var_field, 2660 system, event_name); 2661 2662 if (!ref_field) 2663 hist_err_event("Couldn't find variable: $", 2664 system, event_name, var_name); 2665 2666 return ref_field; 2667 } 2668 2669 static struct ftrace_event_field * 2670 parse_field(struct hist_trigger_data *hist_data, struct trace_event_file *file, 2671 char *field_str, unsigned long *flags) 2672 { 2673 struct ftrace_event_field *field = NULL; 2674 char *field_name, *modifier, *str; 2675 2676 modifier = str = kstrdup(field_str, GFP_KERNEL); 2677 if (!modifier) 2678 return ERR_PTR(-ENOMEM); 2679 2680 field_name = strsep(&modifier, "."); 2681 if (modifier) { 2682 if (strcmp(modifier, "hex") == 0) 2683 *flags |= HIST_FIELD_FL_HEX; 2684 else if (strcmp(modifier, "sym") == 0) 2685 *flags |= HIST_FIELD_FL_SYM; 2686 else if (strcmp(modifier, "sym-offset") == 0) 2687 *flags |= HIST_FIELD_FL_SYM_OFFSET; 2688 else if ((strcmp(modifier, "execname") == 0) && 2689 (strcmp(field_name, "common_pid") == 0)) 2690 *flags |= HIST_FIELD_FL_EXECNAME; 2691 else if (strcmp(modifier, "syscall") == 0) 2692 *flags |= HIST_FIELD_FL_SYSCALL; 2693 else if (strcmp(modifier, "log2") == 0) 2694 *flags |= HIST_FIELD_FL_LOG2; 2695 else if (strcmp(modifier, "usecs") == 0) 2696 *flags |= HIST_FIELD_FL_TIMESTAMP_USECS; 2697 else { 2698 hist_err("Invalid field modifier: ", modifier); 2699 field = ERR_PTR(-EINVAL); 2700 goto out; 2701 } 2702 } 2703 2704 if (strcmp(field_name, "common_timestamp") == 0) { 2705 *flags |= HIST_FIELD_FL_TIMESTAMP; 2706 hist_data->enable_timestamps = true; 2707 if (*flags & HIST_FIELD_FL_TIMESTAMP_USECS) 2708 hist_data->attrs->ts_in_usecs = true; 2709 } else if (strcmp(field_name, "cpu") == 0) 2710 *flags |= HIST_FIELD_FL_CPU; 2711 else { 2712 field = trace_find_event_field(file->event_call, field_name); 2713 if (!field || !field->size) { 2714 hist_err("Couldn't find field: ", field_name); 2715 field = ERR_PTR(-EINVAL); 2716 goto out; 2717 } 2718 } 2719 out: 2720 kfree(str); 2721 2722 return field; 2723 } 2724 2725 static struct hist_field *create_alias(struct hist_trigger_data *hist_data, 2726 struct hist_field *var_ref, 2727 char *var_name) 2728 { 2729 struct hist_field *alias = NULL; 2730 unsigned long flags = HIST_FIELD_FL_ALIAS | HIST_FIELD_FL_VAR; 2731 2732 alias = create_hist_field(hist_data, NULL, flags, var_name); 2733 if (!alias) 2734 return NULL; 2735 2736 alias->fn = var_ref->fn; 2737 alias->operands[0] = var_ref; 2738 2739 if (init_var_ref(alias, var_ref, var_ref->system, var_ref->event_name)) { 2740 destroy_hist_field(alias, 0); 2741 return NULL; 2742 } 2743 2744 return alias; 2745 } 2746 2747 static struct hist_field *parse_atom(struct hist_trigger_data *hist_data, 2748 struct trace_event_file *file, char *str, 2749 unsigned long *flags, char *var_name) 2750 { 2751 char *s, *ref_system = NULL, *ref_event = NULL, *ref_var = str; 2752 struct ftrace_event_field *field = NULL; 2753 struct hist_field *hist_field = NULL; 2754 int ret = 0; 2755 2756 s = strchr(str, '.'); 2757 if (s) { 2758 s = strchr(++s, '.'); 2759 if (s) { 2760 ref_system = strsep(&str, "."); 2761 if (!str) { 2762 ret = -EINVAL; 2763 goto out; 2764 } 2765 ref_event = strsep(&str, "."); 2766 if (!str) { 2767 ret = -EINVAL; 2768 goto out; 2769 } 2770 ref_var = str; 2771 } 2772 } 2773 2774 s = local_field_var_ref(hist_data, ref_system, ref_event, ref_var); 2775 if (!s) { 2776 hist_field = parse_var_ref(hist_data, ref_system, ref_event, ref_var); 2777 if (hist_field) { 2778 if (var_name) { 2779 hist_field = create_alias(hist_data, hist_field, var_name); 2780 if (!hist_field) { 2781 ret = -ENOMEM; 2782 goto out; 2783 } 2784 } 2785 return hist_field; 2786 } 2787 } else 2788 str = s; 2789 2790 field = parse_field(hist_data, file, str, flags); 2791 if (IS_ERR(field)) { 2792 ret = PTR_ERR(field); 2793 goto out; 2794 } 2795 2796 hist_field = create_hist_field(hist_data, field, *flags, var_name); 2797 if (!hist_field) { 2798 ret = -ENOMEM; 2799 goto out; 2800 } 2801 2802 return hist_field; 2803 out: 2804 return ERR_PTR(ret); 2805 } 2806 2807 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2808 struct trace_event_file *file, 2809 char *str, unsigned long flags, 2810 char *var_name, unsigned int level); 2811 2812 static struct hist_field *parse_unary(struct hist_trigger_data *hist_data, 2813 struct trace_event_file *file, 2814 char *str, unsigned long flags, 2815 char *var_name, unsigned int level) 2816 { 2817 struct hist_field *operand1, *expr = NULL; 2818 unsigned long operand_flags; 2819 int ret = 0; 2820 char *s; 2821 2822 /* we support only -(xxx) i.e. explicit parens required */ 2823 2824 if (level > 3) { 2825 hist_err("Too many subexpressions (3 max): ", str); 2826 ret = -EINVAL; 2827 goto free; 2828 } 2829 2830 str++; /* skip leading '-' */ 2831 2832 s = strchr(str, '('); 2833 if (s) 2834 str++; 2835 else { 2836 ret = -EINVAL; 2837 goto free; 2838 } 2839 2840 s = strrchr(str, ')'); 2841 if (s) 2842 *s = '\0'; 2843 else { 2844 ret = -EINVAL; /* no closing ')' */ 2845 goto free; 2846 } 2847 2848 flags |= HIST_FIELD_FL_EXPR; 2849 expr = create_hist_field(hist_data, NULL, flags, var_name); 2850 if (!expr) { 2851 ret = -ENOMEM; 2852 goto free; 2853 } 2854 2855 operand_flags = 0; 2856 operand1 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level); 2857 if (IS_ERR(operand1)) { 2858 ret = PTR_ERR(operand1); 2859 goto free; 2860 } 2861 2862 expr->flags |= operand1->flags & 2863 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2864 expr->fn = hist_field_unary_minus; 2865 expr->operands[0] = operand1; 2866 expr->operator = FIELD_OP_UNARY_MINUS; 2867 expr->name = expr_str(expr, 0); 2868 expr->type = kstrdup(operand1->type, GFP_KERNEL); 2869 if (!expr->type) { 2870 ret = -ENOMEM; 2871 goto free; 2872 } 2873 2874 return expr; 2875 free: 2876 destroy_hist_field(expr, 0); 2877 return ERR_PTR(ret); 2878 } 2879 2880 static int check_expr_operands(struct hist_field *operand1, 2881 struct hist_field *operand2) 2882 { 2883 unsigned long operand1_flags = operand1->flags; 2884 unsigned long operand2_flags = operand2->flags; 2885 2886 if ((operand1_flags & HIST_FIELD_FL_VAR_REF) || 2887 (operand1_flags & HIST_FIELD_FL_ALIAS)) { 2888 struct hist_field *var; 2889 2890 var = find_var_field(operand1->var.hist_data, operand1->name); 2891 if (!var) 2892 return -EINVAL; 2893 operand1_flags = var->flags; 2894 } 2895 2896 if ((operand2_flags & HIST_FIELD_FL_VAR_REF) || 2897 (operand2_flags & HIST_FIELD_FL_ALIAS)) { 2898 struct hist_field *var; 2899 2900 var = find_var_field(operand2->var.hist_data, operand2->name); 2901 if (!var) 2902 return -EINVAL; 2903 operand2_flags = var->flags; 2904 } 2905 2906 if ((operand1_flags & HIST_FIELD_FL_TIMESTAMP_USECS) != 2907 (operand2_flags & HIST_FIELD_FL_TIMESTAMP_USECS)) { 2908 hist_err("Timestamp units in expression don't match", NULL); 2909 return -EINVAL; 2910 } 2911 2912 return 0; 2913 } 2914 2915 static struct hist_field *parse_expr(struct hist_trigger_data *hist_data, 2916 struct trace_event_file *file, 2917 char *str, unsigned long flags, 2918 char *var_name, unsigned int level) 2919 { 2920 struct hist_field *operand1 = NULL, *operand2 = NULL, *expr = NULL; 2921 unsigned long operand_flags; 2922 int field_op, ret = -EINVAL; 2923 char *sep, *operand1_str; 2924 2925 if (level > 3) { 2926 hist_err("Too many subexpressions (3 max): ", str); 2927 return ERR_PTR(-EINVAL); 2928 } 2929 2930 field_op = contains_operator(str); 2931 2932 if (field_op == FIELD_OP_NONE) 2933 return parse_atom(hist_data, file, str, &flags, var_name); 2934 2935 if (field_op == FIELD_OP_UNARY_MINUS) 2936 return parse_unary(hist_data, file, str, flags, var_name, ++level); 2937 2938 switch (field_op) { 2939 case FIELD_OP_MINUS: 2940 sep = "-"; 2941 break; 2942 case FIELD_OP_PLUS: 2943 sep = "+"; 2944 break; 2945 default: 2946 goto free; 2947 } 2948 2949 operand1_str = strsep(&str, sep); 2950 if (!operand1_str || !str) 2951 goto free; 2952 2953 operand_flags = 0; 2954 operand1 = parse_atom(hist_data, file, operand1_str, 2955 &operand_flags, NULL); 2956 if (IS_ERR(operand1)) { 2957 ret = PTR_ERR(operand1); 2958 operand1 = NULL; 2959 goto free; 2960 } 2961 2962 /* rest of string could be another expression e.g. b+c in a+b+c */ 2963 operand_flags = 0; 2964 operand2 = parse_expr(hist_data, file, str, operand_flags, NULL, ++level); 2965 if (IS_ERR(operand2)) { 2966 ret = PTR_ERR(operand2); 2967 operand2 = NULL; 2968 goto free; 2969 } 2970 2971 ret = check_expr_operands(operand1, operand2); 2972 if (ret) 2973 goto free; 2974 2975 flags |= HIST_FIELD_FL_EXPR; 2976 2977 flags |= operand1->flags & 2978 (HIST_FIELD_FL_TIMESTAMP | HIST_FIELD_FL_TIMESTAMP_USECS); 2979 2980 expr = create_hist_field(hist_data, NULL, flags, var_name); 2981 if (!expr) { 2982 ret = -ENOMEM; 2983 goto free; 2984 } 2985 2986 operand1->read_once = true; 2987 operand2->read_once = true; 2988 2989 expr->operands[0] = operand1; 2990 expr->operands[1] = operand2; 2991 expr->operator = field_op; 2992 expr->name = expr_str(expr, 0); 2993 expr->type = kstrdup(operand1->type, GFP_KERNEL); 2994 if (!expr->type) { 2995 ret = -ENOMEM; 2996 goto free; 2997 } 2998 2999 switch (field_op) { 3000 case FIELD_OP_MINUS: 3001 expr->fn = hist_field_minus; 3002 break; 3003 case FIELD_OP_PLUS: 3004 expr->fn = hist_field_plus; 3005 break; 3006 default: 3007 ret = -EINVAL; 3008 goto free; 3009 } 3010 3011 return expr; 3012 free: 3013 destroy_hist_field(operand1, 0); 3014 destroy_hist_field(operand2, 0); 3015 destroy_hist_field(expr, 0); 3016 3017 return ERR_PTR(ret); 3018 } 3019 3020 static char *find_trigger_filter(struct hist_trigger_data *hist_data, 3021 struct trace_event_file *file) 3022 { 3023 struct event_trigger_data *test; 3024 3025 list_for_each_entry_rcu(test, &file->triggers, list) { 3026 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 3027 if (test->private_data == hist_data) 3028 return test->filter_str; 3029 } 3030 } 3031 3032 return NULL; 3033 } 3034 3035 static struct event_command trigger_hist_cmd; 3036 static int event_hist_trigger_func(struct event_command *cmd_ops, 3037 struct trace_event_file *file, 3038 char *glob, char *cmd, char *param); 3039 3040 static bool compatible_keys(struct hist_trigger_data *target_hist_data, 3041 struct hist_trigger_data *hist_data, 3042 unsigned int n_keys) 3043 { 3044 struct hist_field *target_hist_field, *hist_field; 3045 unsigned int n, i, j; 3046 3047 if (hist_data->n_fields - hist_data->n_vals != n_keys) 3048 return false; 3049 3050 i = hist_data->n_vals; 3051 j = target_hist_data->n_vals; 3052 3053 for (n = 0; n < n_keys; n++) { 3054 hist_field = hist_data->fields[i + n]; 3055 target_hist_field = target_hist_data->fields[j + n]; 3056 3057 if (strcmp(hist_field->type, target_hist_field->type) != 0) 3058 return false; 3059 if (hist_field->size != target_hist_field->size) 3060 return false; 3061 if (hist_field->is_signed != target_hist_field->is_signed) 3062 return false; 3063 } 3064 3065 return true; 3066 } 3067 3068 static struct hist_trigger_data * 3069 find_compatible_hist(struct hist_trigger_data *target_hist_data, 3070 struct trace_event_file *file) 3071 { 3072 struct hist_trigger_data *hist_data; 3073 struct event_trigger_data *test; 3074 unsigned int n_keys; 3075 3076 n_keys = target_hist_data->n_fields - target_hist_data->n_vals; 3077 3078 list_for_each_entry_rcu(test, &file->triggers, list) { 3079 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 3080 hist_data = test->private_data; 3081 3082 if (compatible_keys(target_hist_data, hist_data, n_keys)) 3083 return hist_data; 3084 } 3085 } 3086 3087 return NULL; 3088 } 3089 3090 static struct trace_event_file *event_file(struct trace_array *tr, 3091 char *system, char *event_name) 3092 { 3093 struct trace_event_file *file; 3094 3095 file = __find_event_file(tr, system, event_name); 3096 if (!file) 3097 return ERR_PTR(-EINVAL); 3098 3099 return file; 3100 } 3101 3102 static struct hist_field * 3103 find_synthetic_field_var(struct hist_trigger_data *target_hist_data, 3104 char *system, char *event_name, char *field_name) 3105 { 3106 struct hist_field *event_var; 3107 char *synthetic_name; 3108 3109 synthetic_name = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 3110 if (!synthetic_name) 3111 return ERR_PTR(-ENOMEM); 3112 3113 strcpy(synthetic_name, "synthetic_"); 3114 strcat(synthetic_name, field_name); 3115 3116 event_var = find_event_var(target_hist_data, system, event_name, synthetic_name); 3117 3118 kfree(synthetic_name); 3119 3120 return event_var; 3121 } 3122 3123 /** 3124 * create_field_var_hist - Automatically create a histogram and var for a field 3125 * @target_hist_data: The target hist trigger 3126 * @subsys_name: Optional subsystem name 3127 * @event_name: Optional event name 3128 * @field_name: The name of the field (and the resulting variable) 3129 * 3130 * Hist trigger actions fetch data from variables, not directly from 3131 * events. However, for convenience, users are allowed to directly 3132 * specify an event field in an action, which will be automatically 3133 * converted into a variable on their behalf. 3134 3135 * If a user specifies a field on an event that isn't the event the 3136 * histogram currently being defined (the target event histogram), the 3137 * only way that can be accomplished is if a new hist trigger is 3138 * created and the field variable defined on that. 3139 * 3140 * This function creates a new histogram compatible with the target 3141 * event (meaning a histogram with the same key as the target 3142 * histogram), and creates a variable for the specified field, but 3143 * with 'synthetic_' prepended to the variable name in order to avoid 3144 * collision with normal field variables. 3145 * 3146 * Return: The variable created for the field. 3147 */ 3148 static struct hist_field * 3149 create_field_var_hist(struct hist_trigger_data *target_hist_data, 3150 char *subsys_name, char *event_name, char *field_name) 3151 { 3152 struct trace_array *tr = target_hist_data->event_file->tr; 3153 struct hist_field *event_var = ERR_PTR(-EINVAL); 3154 struct hist_trigger_data *hist_data; 3155 unsigned int i, n, first = true; 3156 struct field_var_hist *var_hist; 3157 struct trace_event_file *file; 3158 struct hist_field *key_field; 3159 char *saved_filter; 3160 char *cmd; 3161 int ret; 3162 3163 if (target_hist_data->n_field_var_hists >= SYNTH_FIELDS_MAX) { 3164 hist_err_event("trace action: Too many field variables defined: ", 3165 subsys_name, event_name, field_name); 3166 return ERR_PTR(-EINVAL); 3167 } 3168 3169 file = event_file(tr, subsys_name, event_name); 3170 3171 if (IS_ERR(file)) { 3172 hist_err_event("trace action: Event file not found: ", 3173 subsys_name, event_name, field_name); 3174 ret = PTR_ERR(file); 3175 return ERR_PTR(ret); 3176 } 3177 3178 /* 3179 * Look for a histogram compatible with target. We'll use the 3180 * found histogram specification to create a new matching 3181 * histogram with our variable on it. target_hist_data is not 3182 * yet a registered histogram so we can't use that. 3183 */ 3184 hist_data = find_compatible_hist(target_hist_data, file); 3185 if (!hist_data) { 3186 hist_err_event("trace action: Matching event histogram not found: ", 3187 subsys_name, event_name, field_name); 3188 return ERR_PTR(-EINVAL); 3189 } 3190 3191 /* See if a synthetic field variable has already been created */ 3192 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 3193 event_name, field_name); 3194 if (!IS_ERR_OR_NULL(event_var)) 3195 return event_var; 3196 3197 var_hist = kzalloc(sizeof(*var_hist), GFP_KERNEL); 3198 if (!var_hist) 3199 return ERR_PTR(-ENOMEM); 3200 3201 cmd = kzalloc(MAX_FILTER_STR_VAL, GFP_KERNEL); 3202 if (!cmd) { 3203 kfree(var_hist); 3204 return ERR_PTR(-ENOMEM); 3205 } 3206 3207 /* Use the same keys as the compatible histogram */ 3208 strcat(cmd, "keys="); 3209 3210 for_each_hist_key_field(i, hist_data) { 3211 key_field = hist_data->fields[i]; 3212 if (!first) 3213 strcat(cmd, ","); 3214 strcat(cmd, key_field->field->name); 3215 first = false; 3216 } 3217 3218 /* Create the synthetic field variable specification */ 3219 strcat(cmd, ":synthetic_"); 3220 strcat(cmd, field_name); 3221 strcat(cmd, "="); 3222 strcat(cmd, field_name); 3223 3224 /* Use the same filter as the compatible histogram */ 3225 saved_filter = find_trigger_filter(hist_data, file); 3226 if (saved_filter) { 3227 strcat(cmd, " if "); 3228 strcat(cmd, saved_filter); 3229 } 3230 3231 var_hist->cmd = kstrdup(cmd, GFP_KERNEL); 3232 if (!var_hist->cmd) { 3233 kfree(cmd); 3234 kfree(var_hist); 3235 return ERR_PTR(-ENOMEM); 3236 } 3237 3238 /* Save the compatible histogram information */ 3239 var_hist->hist_data = hist_data; 3240 3241 /* Create the new histogram with our variable */ 3242 ret = event_hist_trigger_func(&trigger_hist_cmd, file, 3243 "", "hist", cmd); 3244 if (ret) { 3245 kfree(cmd); 3246 kfree(var_hist->cmd); 3247 kfree(var_hist); 3248 hist_err_event("trace action: Couldn't create histogram for field: ", 3249 subsys_name, event_name, field_name); 3250 return ERR_PTR(ret); 3251 } 3252 3253 kfree(cmd); 3254 3255 /* If we can't find the variable, something went wrong */ 3256 event_var = find_synthetic_field_var(target_hist_data, subsys_name, 3257 event_name, field_name); 3258 if (IS_ERR_OR_NULL(event_var)) { 3259 kfree(var_hist->cmd); 3260 kfree(var_hist); 3261 hist_err_event("trace action: Couldn't find synthetic variable: ", 3262 subsys_name, event_name, field_name); 3263 return ERR_PTR(-EINVAL); 3264 } 3265 3266 n = target_hist_data->n_field_var_hists; 3267 target_hist_data->field_var_hists[n] = var_hist; 3268 target_hist_data->n_field_var_hists++; 3269 3270 return event_var; 3271 } 3272 3273 static struct hist_field * 3274 find_target_event_var(struct hist_trigger_data *hist_data, 3275 char *subsys_name, char *event_name, char *var_name) 3276 { 3277 struct trace_event_file *file = hist_data->event_file; 3278 struct hist_field *hist_field = NULL; 3279 3280 if (subsys_name) { 3281 struct trace_event_call *call; 3282 3283 if (!event_name) 3284 return NULL; 3285 3286 call = file->event_call; 3287 3288 if (strcmp(subsys_name, call->class->system) != 0) 3289 return NULL; 3290 3291 if (strcmp(event_name, trace_event_name(call)) != 0) 3292 return NULL; 3293 } 3294 3295 hist_field = find_var_field(hist_data, var_name); 3296 3297 return hist_field; 3298 } 3299 3300 static inline void __update_field_vars(struct tracing_map_elt *elt, 3301 struct ring_buffer_event *rbe, 3302 void *rec, 3303 struct field_var **field_vars, 3304 unsigned int n_field_vars, 3305 unsigned int field_var_str_start) 3306 { 3307 struct hist_elt_data *elt_data = elt->private_data; 3308 unsigned int i, j, var_idx; 3309 u64 var_val; 3310 3311 for (i = 0, j = field_var_str_start; i < n_field_vars; i++) { 3312 struct field_var *field_var = field_vars[i]; 3313 struct hist_field *var = field_var->var; 3314 struct hist_field *val = field_var->val; 3315 3316 var_val = val->fn(val, elt, rbe, rec); 3317 var_idx = var->var.idx; 3318 3319 if (val->flags & HIST_FIELD_FL_STRING) { 3320 char *str = elt_data->field_var_str[j++]; 3321 char *val_str = (char *)(uintptr_t)var_val; 3322 3323 strscpy(str, val_str, STR_VAR_LEN_MAX); 3324 var_val = (u64)(uintptr_t)str; 3325 } 3326 tracing_map_set_var(elt, var_idx, var_val); 3327 } 3328 } 3329 3330 static void update_field_vars(struct hist_trigger_data *hist_data, 3331 struct tracing_map_elt *elt, 3332 struct ring_buffer_event *rbe, 3333 void *rec) 3334 { 3335 __update_field_vars(elt, rbe, rec, hist_data->field_vars, 3336 hist_data->n_field_vars, 0); 3337 } 3338 3339 static void save_track_data_vars(struct hist_trigger_data *hist_data, 3340 struct tracing_map_elt *elt, void *rec, 3341 struct ring_buffer_event *rbe, void *key, 3342 struct action_data *data, u64 *var_ref_vals) 3343 { 3344 __update_field_vars(elt, rbe, rec, hist_data->save_vars, 3345 hist_data->n_save_vars, hist_data->n_field_var_str); 3346 } 3347 3348 static struct hist_field *create_var(struct hist_trigger_data *hist_data, 3349 struct trace_event_file *file, 3350 char *name, int size, const char *type) 3351 { 3352 struct hist_field *var; 3353 int idx; 3354 3355 if (find_var(hist_data, file, name) && !hist_data->remove) { 3356 var = ERR_PTR(-EINVAL); 3357 goto out; 3358 } 3359 3360 var = kzalloc(sizeof(struct hist_field), GFP_KERNEL); 3361 if (!var) { 3362 var = ERR_PTR(-ENOMEM); 3363 goto out; 3364 } 3365 3366 idx = tracing_map_add_var(hist_data->map); 3367 if (idx < 0) { 3368 kfree(var); 3369 var = ERR_PTR(-EINVAL); 3370 goto out; 3371 } 3372 3373 var->flags = HIST_FIELD_FL_VAR; 3374 var->var.idx = idx; 3375 var->var.hist_data = var->hist_data = hist_data; 3376 var->size = size; 3377 var->var.name = kstrdup(name, GFP_KERNEL); 3378 var->type = kstrdup(type, GFP_KERNEL); 3379 if (!var->var.name || !var->type) { 3380 kfree(var->var.name); 3381 kfree(var->type); 3382 kfree(var); 3383 var = ERR_PTR(-ENOMEM); 3384 } 3385 out: 3386 return var; 3387 } 3388 3389 static struct field_var *create_field_var(struct hist_trigger_data *hist_data, 3390 struct trace_event_file *file, 3391 char *field_name) 3392 { 3393 struct hist_field *val = NULL, *var = NULL; 3394 unsigned long flags = HIST_FIELD_FL_VAR; 3395 struct field_var *field_var; 3396 int ret = 0; 3397 3398 if (hist_data->n_field_vars >= SYNTH_FIELDS_MAX) { 3399 hist_err("Too many field variables defined: ", field_name); 3400 ret = -EINVAL; 3401 goto err; 3402 } 3403 3404 val = parse_atom(hist_data, file, field_name, &flags, NULL); 3405 if (IS_ERR(val)) { 3406 hist_err("Couldn't parse field variable: ", field_name); 3407 ret = PTR_ERR(val); 3408 goto err; 3409 } 3410 3411 var = create_var(hist_data, file, field_name, val->size, val->type); 3412 if (IS_ERR(var)) { 3413 hist_err("Couldn't create or find variable: ", field_name); 3414 kfree(val); 3415 ret = PTR_ERR(var); 3416 goto err; 3417 } 3418 3419 field_var = kzalloc(sizeof(struct field_var), GFP_KERNEL); 3420 if (!field_var) { 3421 kfree(val); 3422 kfree(var); 3423 ret = -ENOMEM; 3424 goto err; 3425 } 3426 3427 field_var->var = var; 3428 field_var->val = val; 3429 out: 3430 return field_var; 3431 err: 3432 field_var = ERR_PTR(ret); 3433 goto out; 3434 } 3435 3436 /** 3437 * create_target_field_var - Automatically create a variable for a field 3438 * @target_hist_data: The target hist trigger 3439 * @subsys_name: Optional subsystem name 3440 * @event_name: Optional event name 3441 * @var_name: The name of the field (and the resulting variable) 3442 * 3443 * Hist trigger actions fetch data from variables, not directly from 3444 * events. However, for convenience, users are allowed to directly 3445 * specify an event field in an action, which will be automatically 3446 * converted into a variable on their behalf. 3447 3448 * This function creates a field variable with the name var_name on 3449 * the hist trigger currently being defined on the target event. If 3450 * subsys_name and event_name are specified, this function simply 3451 * verifies that they do in fact match the target event subsystem and 3452 * event name. 3453 * 3454 * Return: The variable created for the field. 3455 */ 3456 static struct field_var * 3457 create_target_field_var(struct hist_trigger_data *target_hist_data, 3458 char *subsys_name, char *event_name, char *var_name) 3459 { 3460 struct trace_event_file *file = target_hist_data->event_file; 3461 3462 if (subsys_name) { 3463 struct trace_event_call *call; 3464 3465 if (!event_name) 3466 return NULL; 3467 3468 call = file->event_call; 3469 3470 if (strcmp(subsys_name, call->class->system) != 0) 3471 return NULL; 3472 3473 if (strcmp(event_name, trace_event_name(call)) != 0) 3474 return NULL; 3475 } 3476 3477 return create_field_var(target_hist_data, file, var_name); 3478 } 3479 3480 static bool check_track_val_max(u64 track_val, u64 var_val) 3481 { 3482 if (var_val <= track_val) 3483 return false; 3484 3485 return true; 3486 } 3487 3488 static bool check_track_val_changed(u64 track_val, u64 var_val) 3489 { 3490 if (var_val == track_val) 3491 return false; 3492 3493 return true; 3494 } 3495 3496 static u64 get_track_val(struct hist_trigger_data *hist_data, 3497 struct tracing_map_elt *elt, 3498 struct action_data *data) 3499 { 3500 unsigned int track_var_idx = data->track_data.track_var->var.idx; 3501 u64 track_val; 3502 3503 track_val = tracing_map_read_var(elt, track_var_idx); 3504 3505 return track_val; 3506 } 3507 3508 static void save_track_val(struct hist_trigger_data *hist_data, 3509 struct tracing_map_elt *elt, 3510 struct action_data *data, u64 var_val) 3511 { 3512 unsigned int track_var_idx = data->track_data.track_var->var.idx; 3513 3514 tracing_map_set_var(elt, track_var_idx, var_val); 3515 } 3516 3517 static void save_track_data(struct hist_trigger_data *hist_data, 3518 struct tracing_map_elt *elt, void *rec, 3519 struct ring_buffer_event *rbe, void *key, 3520 struct action_data *data, u64 *var_ref_vals) 3521 { 3522 if (data->track_data.save_data) 3523 data->track_data.save_data(hist_data, elt, rec, rbe, key, data, var_ref_vals); 3524 } 3525 3526 static bool check_track_val(struct tracing_map_elt *elt, 3527 struct action_data *data, 3528 u64 var_val) 3529 { 3530 struct hist_trigger_data *hist_data; 3531 u64 track_val; 3532 3533 hist_data = data->track_data.track_var->hist_data; 3534 track_val = get_track_val(hist_data, elt, data); 3535 3536 return data->track_data.check_val(track_val, var_val); 3537 } 3538 3539 #ifdef CONFIG_TRACER_SNAPSHOT 3540 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3541 { 3542 /* called with tr->max_lock held */ 3543 struct track_data *track_data = tr->cond_snapshot->cond_data; 3544 struct hist_elt_data *elt_data, *track_elt_data; 3545 struct snapshot_context *context = cond_data; 3546 u64 track_val; 3547 3548 if (!track_data) 3549 return false; 3550 3551 track_val = get_track_val(track_data->hist_data, context->elt, 3552 track_data->action_data); 3553 3554 track_data->track_val = track_val; 3555 memcpy(track_data->key, context->key, track_data->key_len); 3556 3557 elt_data = context->elt->private_data; 3558 track_elt_data = track_data->elt.private_data; 3559 if (elt_data->comm) 3560 strncpy(track_elt_data->comm, elt_data->comm, TASK_COMM_LEN); 3561 3562 track_data->updated = true; 3563 3564 return true; 3565 } 3566 3567 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3568 struct tracing_map_elt *elt, void *rec, 3569 struct ring_buffer_event *rbe, void *key, 3570 struct action_data *data, 3571 u64 *var_ref_vals) 3572 { 3573 struct trace_event_file *file = hist_data->event_file; 3574 struct snapshot_context context; 3575 3576 context.elt = elt; 3577 context.key = key; 3578 3579 tracing_snapshot_cond(file->tr, &context); 3580 } 3581 3582 static void hist_trigger_print_key(struct seq_file *m, 3583 struct hist_trigger_data *hist_data, 3584 void *key, 3585 struct tracing_map_elt *elt); 3586 3587 static struct action_data *snapshot_action(struct hist_trigger_data *hist_data) 3588 { 3589 unsigned int i; 3590 3591 if (!hist_data->n_actions) 3592 return NULL; 3593 3594 for (i = 0; i < hist_data->n_actions; i++) { 3595 struct action_data *data = hist_data->actions[i]; 3596 3597 if (data->action == ACTION_SNAPSHOT) 3598 return data; 3599 } 3600 3601 return NULL; 3602 } 3603 3604 static void track_data_snapshot_print(struct seq_file *m, 3605 struct hist_trigger_data *hist_data) 3606 { 3607 struct trace_event_file *file = hist_data->event_file; 3608 struct track_data *track_data; 3609 struct action_data *action; 3610 3611 track_data = tracing_cond_snapshot_data(file->tr); 3612 if (!track_data) 3613 return; 3614 3615 if (!track_data->updated) 3616 return; 3617 3618 action = snapshot_action(hist_data); 3619 if (!action) 3620 return; 3621 3622 seq_puts(m, "\nSnapshot taken (see tracing/snapshot). Details:\n"); 3623 seq_printf(m, "\ttriggering value { %s(%s) }: %10llu", 3624 action->handler == HANDLER_ONMAX ? "onmax" : "onchange", 3625 action->track_data.var_str, track_data->track_val); 3626 3627 seq_puts(m, "\ttriggered by event with key: "); 3628 hist_trigger_print_key(m, hist_data, track_data->key, &track_data->elt); 3629 seq_putc(m, '\n'); 3630 } 3631 #else 3632 static bool cond_snapshot_update(struct trace_array *tr, void *cond_data) 3633 { 3634 return false; 3635 } 3636 static void save_track_data_snapshot(struct hist_trigger_data *hist_data, 3637 struct tracing_map_elt *elt, void *rec, 3638 struct ring_buffer_event *rbe, void *key, 3639 struct action_data *data, 3640 u64 *var_ref_vals) {} 3641 static void track_data_snapshot_print(struct seq_file *m, 3642 struct hist_trigger_data *hist_data) {} 3643 #endif /* CONFIG_TRACER_SNAPSHOT */ 3644 3645 static void track_data_print(struct seq_file *m, 3646 struct hist_trigger_data *hist_data, 3647 struct tracing_map_elt *elt, 3648 struct action_data *data) 3649 { 3650 u64 track_val = get_track_val(hist_data, elt, data); 3651 unsigned int i, save_var_idx; 3652 3653 if (data->handler == HANDLER_ONMAX) 3654 seq_printf(m, "\n\tmax: %10llu", track_val); 3655 else if (data->handler == HANDLER_ONCHANGE) 3656 seq_printf(m, "\n\tchanged: %10llu", track_val); 3657 3658 if (data->action == ACTION_SNAPSHOT) 3659 return; 3660 3661 for (i = 0; i < hist_data->n_save_vars; i++) { 3662 struct hist_field *save_val = hist_data->save_vars[i]->val; 3663 struct hist_field *save_var = hist_data->save_vars[i]->var; 3664 u64 val; 3665 3666 save_var_idx = save_var->var.idx; 3667 3668 val = tracing_map_read_var(elt, save_var_idx); 3669 3670 if (save_val->flags & HIST_FIELD_FL_STRING) { 3671 seq_printf(m, " %s: %-32s", save_var->var.name, 3672 (char *)(uintptr_t)(val)); 3673 } else 3674 seq_printf(m, " %s: %10llu", save_var->var.name, val); 3675 } 3676 } 3677 3678 static void ontrack_action(struct hist_trigger_data *hist_data, 3679 struct tracing_map_elt *elt, void *rec, 3680 struct ring_buffer_event *rbe, void *key, 3681 struct action_data *data, u64 *var_ref_vals) 3682 { 3683 u64 var_val = var_ref_vals[data->track_data.var_ref->var_ref_idx]; 3684 3685 if (check_track_val(elt, data, var_val)) { 3686 save_track_val(hist_data, elt, data, var_val); 3687 save_track_data(hist_data, elt, rec, rbe, key, data, var_ref_vals); 3688 } 3689 } 3690 3691 static void action_data_destroy(struct action_data *data) 3692 { 3693 unsigned int i; 3694 3695 lockdep_assert_held(&event_mutex); 3696 3697 kfree(data->action_name); 3698 3699 for (i = 0; i < data->n_params; i++) 3700 kfree(data->params[i]); 3701 3702 if (data->synth_event) 3703 data->synth_event->ref--; 3704 3705 kfree(data->synth_event_name); 3706 3707 kfree(data); 3708 } 3709 3710 static void track_data_destroy(struct hist_trigger_data *hist_data, 3711 struct action_data *data) 3712 { 3713 struct trace_event_file *file = hist_data->event_file; 3714 3715 destroy_hist_field(data->track_data.track_var, 0); 3716 3717 if (data->action == ACTION_SNAPSHOT) { 3718 struct track_data *track_data; 3719 3720 track_data = tracing_cond_snapshot_data(file->tr); 3721 if (track_data && track_data->hist_data == hist_data) { 3722 tracing_snapshot_cond_disable(file->tr); 3723 track_data_free(track_data); 3724 } 3725 } 3726 3727 kfree(data->track_data.var_str); 3728 3729 action_data_destroy(data); 3730 } 3731 3732 static int action_create(struct hist_trigger_data *hist_data, 3733 struct action_data *data); 3734 3735 static int track_data_create(struct hist_trigger_data *hist_data, 3736 struct action_data *data) 3737 { 3738 struct hist_field *var_field, *ref_field, *track_var = NULL; 3739 struct trace_event_file *file = hist_data->event_file; 3740 char *track_data_var_str; 3741 int ret = 0; 3742 3743 track_data_var_str = data->track_data.var_str; 3744 if (track_data_var_str[0] != '$') { 3745 hist_err("For onmax(x) or onchange(x), x must be a variable: ", track_data_var_str); 3746 return -EINVAL; 3747 } 3748 track_data_var_str++; 3749 3750 var_field = find_target_event_var(hist_data, NULL, NULL, track_data_var_str); 3751 if (!var_field) { 3752 hist_err("Couldn't find onmax or onchange variable: ", track_data_var_str); 3753 return -EINVAL; 3754 } 3755 3756 ref_field = create_var_ref(hist_data, var_field, NULL, NULL); 3757 if (!ref_field) 3758 return -ENOMEM; 3759 3760 data->track_data.var_ref = ref_field; 3761 3762 if (data->handler == HANDLER_ONMAX) 3763 track_var = create_var(hist_data, file, "__max", sizeof(u64), "u64"); 3764 if (IS_ERR(track_var)) { 3765 hist_err("Couldn't create onmax variable: ", "__max"); 3766 ret = PTR_ERR(track_var); 3767 goto out; 3768 } 3769 3770 if (data->handler == HANDLER_ONCHANGE) 3771 track_var = create_var(hist_data, file, "__change", sizeof(u64), "u64"); 3772 if (IS_ERR(track_var)) { 3773 hist_err("Couldn't create onchange variable: ", "__change"); 3774 ret = PTR_ERR(track_var); 3775 goto out; 3776 } 3777 data->track_data.track_var = track_var; 3778 3779 ret = action_create(hist_data, data); 3780 out: 3781 return ret; 3782 } 3783 3784 static int parse_action_params(char *params, struct action_data *data) 3785 { 3786 char *param, *saved_param; 3787 bool first_param = true; 3788 int ret = 0; 3789 3790 while (params) { 3791 if (data->n_params >= SYNTH_FIELDS_MAX) { 3792 hist_err("Too many action params", ""); 3793 goto out; 3794 } 3795 3796 param = strsep(¶ms, ","); 3797 if (!param) { 3798 hist_err("No action param found", ""); 3799 ret = -EINVAL; 3800 goto out; 3801 } 3802 3803 param = strstrip(param); 3804 if (strlen(param) < 2) { 3805 hist_err("Invalid action param: ", param); 3806 ret = -EINVAL; 3807 goto out; 3808 } 3809 3810 saved_param = kstrdup(param, GFP_KERNEL); 3811 if (!saved_param) { 3812 ret = -ENOMEM; 3813 goto out; 3814 } 3815 3816 if (first_param && data->use_trace_keyword) { 3817 data->synth_event_name = saved_param; 3818 first_param = false; 3819 continue; 3820 } 3821 first_param = false; 3822 3823 data->params[data->n_params++] = saved_param; 3824 } 3825 out: 3826 return ret; 3827 } 3828 3829 static int action_parse(char *str, struct action_data *data, 3830 enum handler_id handler) 3831 { 3832 char *action_name; 3833 int ret = 0; 3834 3835 strsep(&str, "."); 3836 if (!str) { 3837 hist_err("action parsing: No action found", ""); 3838 ret = -EINVAL; 3839 goto out; 3840 } 3841 3842 action_name = strsep(&str, "("); 3843 if (!action_name || !str) { 3844 hist_err("action parsing: No action found", ""); 3845 ret = -EINVAL; 3846 goto out; 3847 } 3848 3849 if (str_has_prefix(action_name, "save")) { 3850 char *params = strsep(&str, ")"); 3851 3852 if (!params) { 3853 hist_err("action parsing: No params found for %s", "save"); 3854 ret = -EINVAL; 3855 goto out; 3856 } 3857 3858 ret = parse_action_params(params, data); 3859 if (ret) 3860 goto out; 3861 3862 if (handler == HANDLER_ONMAX) 3863 data->track_data.check_val = check_track_val_max; 3864 else if (handler == HANDLER_ONCHANGE) 3865 data->track_data.check_val = check_track_val_changed; 3866 else { 3867 hist_err("action parsing: Handler doesn't support action: ", action_name); 3868 ret = -EINVAL; 3869 goto out; 3870 } 3871 3872 data->track_data.save_data = save_track_data_vars; 3873 data->fn = ontrack_action; 3874 data->action = ACTION_SAVE; 3875 } else if (str_has_prefix(action_name, "snapshot")) { 3876 char *params = strsep(&str, ")"); 3877 3878 if (!str) { 3879 hist_err("action parsing: No closing paren found: %s", params); 3880 ret = -EINVAL; 3881 goto out; 3882 } 3883 3884 if (handler == HANDLER_ONMAX) 3885 data->track_data.check_val = check_track_val_max; 3886 else if (handler == HANDLER_ONCHANGE) 3887 data->track_data.check_val = check_track_val_changed; 3888 else { 3889 hist_err("action parsing: Handler doesn't support action: ", action_name); 3890 ret = -EINVAL; 3891 goto out; 3892 } 3893 3894 data->track_data.save_data = save_track_data_snapshot; 3895 data->fn = ontrack_action; 3896 data->action = ACTION_SNAPSHOT; 3897 } else { 3898 char *params = strsep(&str, ")"); 3899 3900 if (str_has_prefix(action_name, "trace")) 3901 data->use_trace_keyword = true; 3902 3903 if (params) { 3904 ret = parse_action_params(params, data); 3905 if (ret) 3906 goto out; 3907 } 3908 3909 if (handler == HANDLER_ONMAX) 3910 data->track_data.check_val = check_track_val_max; 3911 else if (handler == HANDLER_ONCHANGE) 3912 data->track_data.check_val = check_track_val_changed; 3913 3914 if (handler != HANDLER_ONMATCH) { 3915 data->track_data.save_data = action_trace; 3916 data->fn = ontrack_action; 3917 } else 3918 data->fn = action_trace; 3919 3920 data->action = ACTION_TRACE; 3921 } 3922 3923 data->action_name = kstrdup(action_name, GFP_KERNEL); 3924 if (!data->action_name) { 3925 ret = -ENOMEM; 3926 goto out; 3927 } 3928 3929 data->handler = handler; 3930 out: 3931 return ret; 3932 } 3933 3934 static struct action_data *track_data_parse(struct hist_trigger_data *hist_data, 3935 char *str, enum handler_id handler) 3936 { 3937 struct action_data *data; 3938 int ret = -EINVAL; 3939 char *var_str; 3940 3941 data = kzalloc(sizeof(*data), GFP_KERNEL); 3942 if (!data) 3943 return ERR_PTR(-ENOMEM); 3944 3945 var_str = strsep(&str, ")"); 3946 if (!var_str || !str) { 3947 ret = -EINVAL; 3948 goto free; 3949 } 3950 3951 data->track_data.var_str = kstrdup(var_str, GFP_KERNEL); 3952 if (!data->track_data.var_str) { 3953 ret = -ENOMEM; 3954 goto free; 3955 } 3956 3957 ret = action_parse(str, data, handler); 3958 if (ret) 3959 goto free; 3960 out: 3961 return data; 3962 free: 3963 track_data_destroy(hist_data, data); 3964 data = ERR_PTR(ret); 3965 goto out; 3966 } 3967 3968 static void onmatch_destroy(struct action_data *data) 3969 { 3970 kfree(data->match_data.event); 3971 kfree(data->match_data.event_system); 3972 3973 action_data_destroy(data); 3974 } 3975 3976 static void destroy_field_var(struct field_var *field_var) 3977 { 3978 if (!field_var) 3979 return; 3980 3981 destroy_hist_field(field_var->var, 0); 3982 destroy_hist_field(field_var->val, 0); 3983 3984 kfree(field_var); 3985 } 3986 3987 static void destroy_field_vars(struct hist_trigger_data *hist_data) 3988 { 3989 unsigned int i; 3990 3991 for (i = 0; i < hist_data->n_field_vars; i++) 3992 destroy_field_var(hist_data->field_vars[i]); 3993 } 3994 3995 static void save_field_var(struct hist_trigger_data *hist_data, 3996 struct field_var *field_var) 3997 { 3998 hist_data->field_vars[hist_data->n_field_vars++] = field_var; 3999 4000 if (field_var->val->flags & HIST_FIELD_FL_STRING) 4001 hist_data->n_field_var_str++; 4002 } 4003 4004 4005 static int check_synth_field(struct synth_event *event, 4006 struct hist_field *hist_field, 4007 unsigned int field_pos) 4008 { 4009 struct synth_field *field; 4010 4011 if (field_pos >= event->n_fields) 4012 return -EINVAL; 4013 4014 field = event->fields[field_pos]; 4015 4016 if (strcmp(field->type, hist_field->type) != 0) 4017 return -EINVAL; 4018 4019 return 0; 4020 } 4021 4022 static struct hist_field * 4023 trace_action_find_var(struct hist_trigger_data *hist_data, 4024 struct action_data *data, 4025 char *system, char *event, char *var) 4026 { 4027 struct hist_field *hist_field; 4028 4029 var++; /* skip '$' */ 4030 4031 hist_field = find_target_event_var(hist_data, system, event, var); 4032 if (!hist_field) { 4033 if (!system && data->handler == HANDLER_ONMATCH) { 4034 system = data->match_data.event_system; 4035 event = data->match_data.event; 4036 } 4037 4038 hist_field = find_event_var(hist_data, system, event, var); 4039 } 4040 4041 if (!hist_field) 4042 hist_err_event("trace action: Couldn't find param: $", system, event, var); 4043 4044 return hist_field; 4045 } 4046 4047 static struct hist_field * 4048 trace_action_create_field_var(struct hist_trigger_data *hist_data, 4049 struct action_data *data, char *system, 4050 char *event, char *var) 4051 { 4052 struct hist_field *hist_field = NULL; 4053 struct field_var *field_var; 4054 4055 /* 4056 * First try to create a field var on the target event (the 4057 * currently being defined). This will create a variable for 4058 * unqualified fields on the target event, or if qualified, 4059 * target fields that have qualified names matching the target. 4060 */ 4061 field_var = create_target_field_var(hist_data, system, event, var); 4062 4063 if (field_var && !IS_ERR(field_var)) { 4064 save_field_var(hist_data, field_var); 4065 hist_field = field_var->var; 4066 } else { 4067 field_var = NULL; 4068 /* 4069 * If no explicit system.event is specfied, default to 4070 * looking for fields on the onmatch(system.event.xxx) 4071 * event. 4072 */ 4073 if (!system && data->handler == HANDLER_ONMATCH) { 4074 system = data->match_data.event_system; 4075 event = data->match_data.event; 4076 } 4077 4078 /* 4079 * At this point, we're looking at a field on another 4080 * event. Because we can't modify a hist trigger on 4081 * another event to add a variable for a field, we need 4082 * to create a new trigger on that event and create the 4083 * variable at the same time. 4084 */ 4085 hist_field = create_field_var_hist(hist_data, system, event, var); 4086 if (IS_ERR(hist_field)) 4087 goto free; 4088 } 4089 out: 4090 return hist_field; 4091 free: 4092 destroy_field_var(field_var); 4093 hist_field = NULL; 4094 goto out; 4095 } 4096 4097 static int trace_action_create(struct hist_trigger_data *hist_data, 4098 struct action_data *data) 4099 { 4100 char *event_name, *param, *system = NULL; 4101 struct hist_field *hist_field, *var_ref; 4102 unsigned int i, var_ref_idx; 4103 unsigned int field_pos = 0; 4104 struct synth_event *event; 4105 char *synth_event_name; 4106 int ret = 0; 4107 4108 lockdep_assert_held(&event_mutex); 4109 4110 if (data->use_trace_keyword) 4111 synth_event_name = data->synth_event_name; 4112 else 4113 synth_event_name = data->action_name; 4114 4115 event = find_synth_event(synth_event_name); 4116 if (!event) { 4117 hist_err("trace action: Couldn't find synthetic event: ", synth_event_name); 4118 return -EINVAL; 4119 } 4120 4121 event->ref++; 4122 4123 var_ref_idx = hist_data->n_var_refs; 4124 4125 for (i = 0; i < data->n_params; i++) { 4126 char *p; 4127 4128 p = param = kstrdup(data->params[i], GFP_KERNEL); 4129 if (!param) { 4130 ret = -ENOMEM; 4131 goto err; 4132 } 4133 4134 system = strsep(¶m, "."); 4135 if (!param) { 4136 param = (char *)system; 4137 system = event_name = NULL; 4138 } else { 4139 event_name = strsep(¶m, "."); 4140 if (!param) { 4141 kfree(p); 4142 ret = -EINVAL; 4143 goto err; 4144 } 4145 } 4146 4147 if (param[0] == '$') 4148 hist_field = trace_action_find_var(hist_data, data, 4149 system, event_name, 4150 param); 4151 else 4152 hist_field = trace_action_create_field_var(hist_data, 4153 data, 4154 system, 4155 event_name, 4156 param); 4157 4158 if (!hist_field) { 4159 kfree(p); 4160 ret = -EINVAL; 4161 goto err; 4162 } 4163 4164 if (check_synth_field(event, hist_field, field_pos) == 0) { 4165 var_ref = create_var_ref(hist_data, hist_field, 4166 system, event_name); 4167 if (!var_ref) { 4168 kfree(p); 4169 ret = -ENOMEM; 4170 goto err; 4171 } 4172 4173 field_pos++; 4174 kfree(p); 4175 continue; 4176 } 4177 4178 hist_err_event("trace action: Param type doesn't match synthetic event field type: ", 4179 system, event_name, param); 4180 kfree(p); 4181 ret = -EINVAL; 4182 goto err; 4183 } 4184 4185 if (field_pos != event->n_fields) { 4186 hist_err("trace action: Param count doesn't match synthetic event field count: ", event->name); 4187 ret = -EINVAL; 4188 goto err; 4189 } 4190 4191 data->synth_event = event; 4192 data->var_ref_idx = var_ref_idx; 4193 out: 4194 return ret; 4195 err: 4196 event->ref--; 4197 4198 goto out; 4199 } 4200 4201 static int action_create(struct hist_trigger_data *hist_data, 4202 struct action_data *data) 4203 { 4204 struct trace_event_file *file = hist_data->event_file; 4205 struct track_data *track_data; 4206 struct field_var *field_var; 4207 unsigned int i; 4208 char *param; 4209 int ret = 0; 4210 4211 if (data->action == ACTION_TRACE) 4212 return trace_action_create(hist_data, data); 4213 4214 if (data->action == ACTION_SNAPSHOT) { 4215 track_data = track_data_alloc(hist_data->key_size, data, hist_data); 4216 if (IS_ERR(track_data)) { 4217 ret = PTR_ERR(track_data); 4218 goto out; 4219 } 4220 4221 ret = tracing_snapshot_cond_enable(file->tr, track_data, 4222 cond_snapshot_update); 4223 if (ret) 4224 track_data_free(track_data); 4225 4226 goto out; 4227 } 4228 4229 if (data->action == ACTION_SAVE) { 4230 if (hist_data->n_save_vars) { 4231 ret = -EEXIST; 4232 hist_err("save action: Can't have more than one save() action per hist", ""); 4233 goto out; 4234 } 4235 4236 for (i = 0; i < data->n_params; i++) { 4237 param = kstrdup(data->params[i], GFP_KERNEL); 4238 if (!param) { 4239 ret = -ENOMEM; 4240 goto out; 4241 } 4242 4243 field_var = create_target_field_var(hist_data, NULL, NULL, param); 4244 if (IS_ERR(field_var)) { 4245 hist_err("save action: Couldn't create field variable: ", param); 4246 ret = PTR_ERR(field_var); 4247 kfree(param); 4248 goto out; 4249 } 4250 4251 hist_data->save_vars[hist_data->n_save_vars++] = field_var; 4252 if (field_var->val->flags & HIST_FIELD_FL_STRING) 4253 hist_data->n_save_var_str++; 4254 kfree(param); 4255 } 4256 } 4257 out: 4258 return ret; 4259 } 4260 4261 static int onmatch_create(struct hist_trigger_data *hist_data, 4262 struct action_data *data) 4263 { 4264 return action_create(hist_data, data); 4265 } 4266 4267 static struct action_data *onmatch_parse(struct trace_array *tr, char *str) 4268 { 4269 char *match_event, *match_event_system; 4270 struct action_data *data; 4271 int ret = -EINVAL; 4272 4273 data = kzalloc(sizeof(*data), GFP_KERNEL); 4274 if (!data) 4275 return ERR_PTR(-ENOMEM); 4276 4277 match_event = strsep(&str, ")"); 4278 if (!match_event || !str) { 4279 hist_err("onmatch: Missing closing paren: ", match_event); 4280 goto free; 4281 } 4282 4283 match_event_system = strsep(&match_event, "."); 4284 if (!match_event) { 4285 hist_err("onmatch: Missing subsystem for match event: ", match_event_system); 4286 goto free; 4287 } 4288 4289 if (IS_ERR(event_file(tr, match_event_system, match_event))) { 4290 hist_err_event("onmatch: Invalid subsystem or event name: ", 4291 match_event_system, match_event, NULL); 4292 goto free; 4293 } 4294 4295 data->match_data.event = kstrdup(match_event, GFP_KERNEL); 4296 if (!data->match_data.event) { 4297 ret = -ENOMEM; 4298 goto free; 4299 } 4300 4301 data->match_data.event_system = kstrdup(match_event_system, GFP_KERNEL); 4302 if (!data->match_data.event_system) { 4303 ret = -ENOMEM; 4304 goto free; 4305 } 4306 4307 ret = action_parse(str, data, HANDLER_ONMATCH); 4308 if (ret) 4309 goto free; 4310 out: 4311 return data; 4312 free: 4313 onmatch_destroy(data); 4314 data = ERR_PTR(ret); 4315 goto out; 4316 } 4317 4318 static int create_hitcount_val(struct hist_trigger_data *hist_data) 4319 { 4320 hist_data->fields[HITCOUNT_IDX] = 4321 create_hist_field(hist_data, NULL, HIST_FIELD_FL_HITCOUNT, NULL); 4322 if (!hist_data->fields[HITCOUNT_IDX]) 4323 return -ENOMEM; 4324 4325 hist_data->n_vals++; 4326 hist_data->n_fields++; 4327 4328 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX)) 4329 return -EINVAL; 4330 4331 return 0; 4332 } 4333 4334 static int __create_val_field(struct hist_trigger_data *hist_data, 4335 unsigned int val_idx, 4336 struct trace_event_file *file, 4337 char *var_name, char *field_str, 4338 unsigned long flags) 4339 { 4340 struct hist_field *hist_field; 4341 int ret = 0; 4342 4343 hist_field = parse_expr(hist_data, file, field_str, flags, var_name, 0); 4344 if (IS_ERR(hist_field)) { 4345 ret = PTR_ERR(hist_field); 4346 goto out; 4347 } 4348 4349 hist_data->fields[val_idx] = hist_field; 4350 4351 ++hist_data->n_vals; 4352 ++hist_data->n_fields; 4353 4354 if (WARN_ON(hist_data->n_vals > TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 4355 ret = -EINVAL; 4356 out: 4357 return ret; 4358 } 4359 4360 static int create_val_field(struct hist_trigger_data *hist_data, 4361 unsigned int val_idx, 4362 struct trace_event_file *file, 4363 char *field_str) 4364 { 4365 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX)) 4366 return -EINVAL; 4367 4368 return __create_val_field(hist_data, val_idx, file, NULL, field_str, 0); 4369 } 4370 4371 static int create_var_field(struct hist_trigger_data *hist_data, 4372 unsigned int val_idx, 4373 struct trace_event_file *file, 4374 char *var_name, char *expr_str) 4375 { 4376 unsigned long flags = 0; 4377 4378 if (WARN_ON(val_idx >= TRACING_MAP_VALS_MAX + TRACING_MAP_VARS_MAX)) 4379 return -EINVAL; 4380 4381 if (find_var(hist_data, file, var_name) && !hist_data->remove) { 4382 hist_err("Variable already defined: ", var_name); 4383 return -EINVAL; 4384 } 4385 4386 flags |= HIST_FIELD_FL_VAR; 4387 hist_data->n_vars++; 4388 if (WARN_ON(hist_data->n_vars > TRACING_MAP_VARS_MAX)) 4389 return -EINVAL; 4390 4391 return __create_val_field(hist_data, val_idx, file, var_name, expr_str, flags); 4392 } 4393 4394 static int create_val_fields(struct hist_trigger_data *hist_data, 4395 struct trace_event_file *file) 4396 { 4397 char *fields_str, *field_str; 4398 unsigned int i, j = 1; 4399 int ret; 4400 4401 ret = create_hitcount_val(hist_data); 4402 if (ret) 4403 goto out; 4404 4405 fields_str = hist_data->attrs->vals_str; 4406 if (!fields_str) 4407 goto out; 4408 4409 strsep(&fields_str, "="); 4410 if (!fields_str) 4411 goto out; 4412 4413 for (i = 0, j = 1; i < TRACING_MAP_VALS_MAX && 4414 j < TRACING_MAP_VALS_MAX; i++) { 4415 field_str = strsep(&fields_str, ","); 4416 if (!field_str) 4417 break; 4418 4419 if (strcmp(field_str, "hitcount") == 0) 4420 continue; 4421 4422 ret = create_val_field(hist_data, j++, file, field_str); 4423 if (ret) 4424 goto out; 4425 } 4426 4427 if (fields_str && (strcmp(fields_str, "hitcount") != 0)) 4428 ret = -EINVAL; 4429 out: 4430 return ret; 4431 } 4432 4433 static int create_key_field(struct hist_trigger_data *hist_data, 4434 unsigned int key_idx, 4435 unsigned int key_offset, 4436 struct trace_event_file *file, 4437 char *field_str) 4438 { 4439 struct hist_field *hist_field = NULL; 4440 4441 unsigned long flags = 0; 4442 unsigned int key_size; 4443 int ret = 0; 4444 4445 if (WARN_ON(key_idx >= HIST_FIELDS_MAX)) 4446 return -EINVAL; 4447 4448 flags |= HIST_FIELD_FL_KEY; 4449 4450 if (strcmp(field_str, "stacktrace") == 0) { 4451 flags |= HIST_FIELD_FL_STACKTRACE; 4452 key_size = sizeof(unsigned long) * HIST_STACKTRACE_DEPTH; 4453 hist_field = create_hist_field(hist_data, NULL, flags, NULL); 4454 } else { 4455 hist_field = parse_expr(hist_data, file, field_str, flags, 4456 NULL, 0); 4457 if (IS_ERR(hist_field)) { 4458 ret = PTR_ERR(hist_field); 4459 goto out; 4460 } 4461 4462 if (hist_field->flags & HIST_FIELD_FL_VAR_REF) { 4463 hist_err("Using variable references as keys not supported: ", field_str); 4464 destroy_hist_field(hist_field, 0); 4465 ret = -EINVAL; 4466 goto out; 4467 } 4468 4469 key_size = hist_field->size; 4470 } 4471 4472 hist_data->fields[key_idx] = hist_field; 4473 4474 key_size = ALIGN(key_size, sizeof(u64)); 4475 hist_data->fields[key_idx]->size = key_size; 4476 hist_data->fields[key_idx]->offset = key_offset; 4477 4478 hist_data->key_size += key_size; 4479 4480 if (hist_data->key_size > HIST_KEY_SIZE_MAX) { 4481 ret = -EINVAL; 4482 goto out; 4483 } 4484 4485 hist_data->n_keys++; 4486 hist_data->n_fields++; 4487 4488 if (WARN_ON(hist_data->n_keys > TRACING_MAP_KEYS_MAX)) 4489 return -EINVAL; 4490 4491 ret = key_size; 4492 out: 4493 return ret; 4494 } 4495 4496 static int create_key_fields(struct hist_trigger_data *hist_data, 4497 struct trace_event_file *file) 4498 { 4499 unsigned int i, key_offset = 0, n_vals = hist_data->n_vals; 4500 char *fields_str, *field_str; 4501 int ret = -EINVAL; 4502 4503 fields_str = hist_data->attrs->keys_str; 4504 if (!fields_str) 4505 goto out; 4506 4507 strsep(&fields_str, "="); 4508 if (!fields_str) 4509 goto out; 4510 4511 for (i = n_vals; i < n_vals + TRACING_MAP_KEYS_MAX; i++) { 4512 field_str = strsep(&fields_str, ","); 4513 if (!field_str) 4514 break; 4515 ret = create_key_field(hist_data, i, key_offset, 4516 file, field_str); 4517 if (ret < 0) 4518 goto out; 4519 key_offset += ret; 4520 } 4521 if (fields_str) { 4522 ret = -EINVAL; 4523 goto out; 4524 } 4525 ret = 0; 4526 out: 4527 return ret; 4528 } 4529 4530 static int create_var_fields(struct hist_trigger_data *hist_data, 4531 struct trace_event_file *file) 4532 { 4533 unsigned int i, j = hist_data->n_vals; 4534 int ret = 0; 4535 4536 unsigned int n_vars = hist_data->attrs->var_defs.n_vars; 4537 4538 for (i = 0; i < n_vars; i++) { 4539 char *var_name = hist_data->attrs->var_defs.name[i]; 4540 char *expr = hist_data->attrs->var_defs.expr[i]; 4541 4542 ret = create_var_field(hist_data, j++, file, var_name, expr); 4543 if (ret) 4544 goto out; 4545 } 4546 out: 4547 return ret; 4548 } 4549 4550 static void free_var_defs(struct hist_trigger_data *hist_data) 4551 { 4552 unsigned int i; 4553 4554 for (i = 0; i < hist_data->attrs->var_defs.n_vars; i++) { 4555 kfree(hist_data->attrs->var_defs.name[i]); 4556 kfree(hist_data->attrs->var_defs.expr[i]); 4557 } 4558 4559 hist_data->attrs->var_defs.n_vars = 0; 4560 } 4561 4562 static int parse_var_defs(struct hist_trigger_data *hist_data) 4563 { 4564 char *s, *str, *var_name, *field_str; 4565 unsigned int i, j, n_vars = 0; 4566 int ret = 0; 4567 4568 for (i = 0; i < hist_data->attrs->n_assignments; i++) { 4569 str = hist_data->attrs->assignment_str[i]; 4570 for (j = 0; j < TRACING_MAP_VARS_MAX; j++) { 4571 field_str = strsep(&str, ","); 4572 if (!field_str) 4573 break; 4574 4575 var_name = strsep(&field_str, "="); 4576 if (!var_name || !field_str) { 4577 hist_err("Malformed assignment: ", var_name); 4578 ret = -EINVAL; 4579 goto free; 4580 } 4581 4582 if (n_vars == TRACING_MAP_VARS_MAX) { 4583 hist_err("Too many variables defined: ", var_name); 4584 ret = -EINVAL; 4585 goto free; 4586 } 4587 4588 s = kstrdup(var_name, GFP_KERNEL); 4589 if (!s) { 4590 ret = -ENOMEM; 4591 goto free; 4592 } 4593 hist_data->attrs->var_defs.name[n_vars] = s; 4594 4595 s = kstrdup(field_str, GFP_KERNEL); 4596 if (!s) { 4597 kfree(hist_data->attrs->var_defs.name[n_vars]); 4598 ret = -ENOMEM; 4599 goto free; 4600 } 4601 hist_data->attrs->var_defs.expr[n_vars++] = s; 4602 4603 hist_data->attrs->var_defs.n_vars = n_vars; 4604 } 4605 } 4606 4607 return ret; 4608 free: 4609 free_var_defs(hist_data); 4610 4611 return ret; 4612 } 4613 4614 static int create_hist_fields(struct hist_trigger_data *hist_data, 4615 struct trace_event_file *file) 4616 { 4617 int ret; 4618 4619 ret = parse_var_defs(hist_data); 4620 if (ret) 4621 goto out; 4622 4623 ret = create_val_fields(hist_data, file); 4624 if (ret) 4625 goto out; 4626 4627 ret = create_var_fields(hist_data, file); 4628 if (ret) 4629 goto out; 4630 4631 ret = create_key_fields(hist_data, file); 4632 if (ret) 4633 goto out; 4634 out: 4635 free_var_defs(hist_data); 4636 4637 return ret; 4638 } 4639 4640 static int is_descending(const char *str) 4641 { 4642 if (!str) 4643 return 0; 4644 4645 if (strcmp(str, "descending") == 0) 4646 return 1; 4647 4648 if (strcmp(str, "ascending") == 0) 4649 return 0; 4650 4651 return -EINVAL; 4652 } 4653 4654 static int create_sort_keys(struct hist_trigger_data *hist_data) 4655 { 4656 char *fields_str = hist_data->attrs->sort_key_str; 4657 struct tracing_map_sort_key *sort_key; 4658 int descending, ret = 0; 4659 unsigned int i, j, k; 4660 4661 hist_data->n_sort_keys = 1; /* we always have at least one, hitcount */ 4662 4663 if (!fields_str) 4664 goto out; 4665 4666 strsep(&fields_str, "="); 4667 if (!fields_str) { 4668 ret = -EINVAL; 4669 goto out; 4670 } 4671 4672 for (i = 0; i < TRACING_MAP_SORT_KEYS_MAX; i++) { 4673 struct hist_field *hist_field; 4674 char *field_str, *field_name; 4675 const char *test_name; 4676 4677 sort_key = &hist_data->sort_keys[i]; 4678 4679 field_str = strsep(&fields_str, ","); 4680 if (!field_str) { 4681 if (i == 0) 4682 ret = -EINVAL; 4683 break; 4684 } 4685 4686 if ((i == TRACING_MAP_SORT_KEYS_MAX - 1) && fields_str) { 4687 ret = -EINVAL; 4688 break; 4689 } 4690 4691 field_name = strsep(&field_str, "."); 4692 if (!field_name) { 4693 ret = -EINVAL; 4694 break; 4695 } 4696 4697 if (strcmp(field_name, "hitcount") == 0) { 4698 descending = is_descending(field_str); 4699 if (descending < 0) { 4700 ret = descending; 4701 break; 4702 } 4703 sort_key->descending = descending; 4704 continue; 4705 } 4706 4707 for (j = 1, k = 1; j < hist_data->n_fields; j++) { 4708 unsigned int idx; 4709 4710 hist_field = hist_data->fields[j]; 4711 if (hist_field->flags & HIST_FIELD_FL_VAR) 4712 continue; 4713 4714 idx = k++; 4715 4716 test_name = hist_field_name(hist_field, 0); 4717 4718 if (strcmp(field_name, test_name) == 0) { 4719 sort_key->field_idx = idx; 4720 descending = is_descending(field_str); 4721 if (descending < 0) { 4722 ret = descending; 4723 goto out; 4724 } 4725 sort_key->descending = descending; 4726 break; 4727 } 4728 } 4729 if (j == hist_data->n_fields) { 4730 ret = -EINVAL; 4731 break; 4732 } 4733 } 4734 4735 hist_data->n_sort_keys = i; 4736 out: 4737 return ret; 4738 } 4739 4740 static void destroy_actions(struct hist_trigger_data *hist_data) 4741 { 4742 unsigned int i; 4743 4744 for (i = 0; i < hist_data->n_actions; i++) { 4745 struct action_data *data = hist_data->actions[i]; 4746 4747 if (data->handler == HANDLER_ONMATCH) 4748 onmatch_destroy(data); 4749 else if (data->handler == HANDLER_ONMAX || 4750 data->handler == HANDLER_ONCHANGE) 4751 track_data_destroy(hist_data, data); 4752 else 4753 kfree(data); 4754 } 4755 } 4756 4757 static int parse_actions(struct hist_trigger_data *hist_data) 4758 { 4759 struct trace_array *tr = hist_data->event_file->tr; 4760 struct action_data *data; 4761 unsigned int i; 4762 int ret = 0; 4763 char *str; 4764 int len; 4765 4766 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4767 str = hist_data->attrs->action_str[i]; 4768 4769 if ((len = str_has_prefix(str, "onmatch("))) { 4770 char *action_str = str + len; 4771 4772 data = onmatch_parse(tr, action_str); 4773 if (IS_ERR(data)) { 4774 ret = PTR_ERR(data); 4775 break; 4776 } 4777 } else if ((len = str_has_prefix(str, "onmax("))) { 4778 char *action_str = str + len; 4779 4780 data = track_data_parse(hist_data, action_str, 4781 HANDLER_ONMAX); 4782 if (IS_ERR(data)) { 4783 ret = PTR_ERR(data); 4784 break; 4785 } 4786 } else if ((len = str_has_prefix(str, "onchange("))) { 4787 char *action_str = str + len; 4788 4789 data = track_data_parse(hist_data, action_str, 4790 HANDLER_ONCHANGE); 4791 if (IS_ERR(data)) { 4792 ret = PTR_ERR(data); 4793 break; 4794 } 4795 } else { 4796 ret = -EINVAL; 4797 break; 4798 } 4799 4800 hist_data->actions[hist_data->n_actions++] = data; 4801 } 4802 4803 return ret; 4804 } 4805 4806 static int create_actions(struct hist_trigger_data *hist_data) 4807 { 4808 struct action_data *data; 4809 unsigned int i; 4810 int ret = 0; 4811 4812 for (i = 0; i < hist_data->attrs->n_actions; i++) { 4813 data = hist_data->actions[i]; 4814 4815 if (data->handler == HANDLER_ONMATCH) { 4816 ret = onmatch_create(hist_data, data); 4817 if (ret) 4818 break; 4819 } else if (data->handler == HANDLER_ONMAX || 4820 data->handler == HANDLER_ONCHANGE) { 4821 ret = track_data_create(hist_data, data); 4822 if (ret) 4823 break; 4824 } else { 4825 ret = -EINVAL; 4826 break; 4827 } 4828 } 4829 4830 return ret; 4831 } 4832 4833 static void print_actions(struct seq_file *m, 4834 struct hist_trigger_data *hist_data, 4835 struct tracing_map_elt *elt) 4836 { 4837 unsigned int i; 4838 4839 for (i = 0; i < hist_data->n_actions; i++) { 4840 struct action_data *data = hist_data->actions[i]; 4841 4842 if (data->action == ACTION_SNAPSHOT) 4843 continue; 4844 4845 if (data->handler == HANDLER_ONMAX || 4846 data->handler == HANDLER_ONCHANGE) 4847 track_data_print(m, hist_data, elt, data); 4848 } 4849 } 4850 4851 static void print_action_spec(struct seq_file *m, 4852 struct hist_trigger_data *hist_data, 4853 struct action_data *data) 4854 { 4855 unsigned int i; 4856 4857 if (data->action == ACTION_SAVE) { 4858 for (i = 0; i < hist_data->n_save_vars; i++) { 4859 seq_printf(m, "%s", hist_data->save_vars[i]->var->var.name); 4860 if (i < hist_data->n_save_vars - 1) 4861 seq_puts(m, ","); 4862 } 4863 } else if (data->action == ACTION_TRACE) { 4864 if (data->use_trace_keyword) 4865 seq_printf(m, "%s", data->synth_event_name); 4866 for (i = 0; i < data->n_params; i++) { 4867 if (i || data->use_trace_keyword) 4868 seq_puts(m, ","); 4869 seq_printf(m, "%s", data->params[i]); 4870 } 4871 } 4872 } 4873 4874 static void print_track_data_spec(struct seq_file *m, 4875 struct hist_trigger_data *hist_data, 4876 struct action_data *data) 4877 { 4878 if (data->handler == HANDLER_ONMAX) 4879 seq_puts(m, ":onmax("); 4880 else if (data->handler == HANDLER_ONCHANGE) 4881 seq_puts(m, ":onchange("); 4882 seq_printf(m, "%s", data->track_data.var_str); 4883 seq_printf(m, ").%s(", data->action_name); 4884 4885 print_action_spec(m, hist_data, data); 4886 4887 seq_puts(m, ")"); 4888 } 4889 4890 static void print_onmatch_spec(struct seq_file *m, 4891 struct hist_trigger_data *hist_data, 4892 struct action_data *data) 4893 { 4894 seq_printf(m, ":onmatch(%s.%s).", data->match_data.event_system, 4895 data->match_data.event); 4896 4897 seq_printf(m, "%s(", data->action_name); 4898 4899 print_action_spec(m, hist_data, data); 4900 4901 seq_puts(m, ")"); 4902 } 4903 4904 static bool actions_match(struct hist_trigger_data *hist_data, 4905 struct hist_trigger_data *hist_data_test) 4906 { 4907 unsigned int i, j; 4908 4909 if (hist_data->n_actions != hist_data_test->n_actions) 4910 return false; 4911 4912 for (i = 0; i < hist_data->n_actions; i++) { 4913 struct action_data *data = hist_data->actions[i]; 4914 struct action_data *data_test = hist_data_test->actions[i]; 4915 char *action_name, *action_name_test; 4916 4917 if (data->handler != data_test->handler) 4918 return false; 4919 if (data->action != data_test->action) 4920 return false; 4921 4922 if (data->n_params != data_test->n_params) 4923 return false; 4924 4925 for (j = 0; j < data->n_params; j++) { 4926 if (strcmp(data->params[j], data_test->params[j]) != 0) 4927 return false; 4928 } 4929 4930 if (data->use_trace_keyword) 4931 action_name = data->synth_event_name; 4932 else 4933 action_name = data->action_name; 4934 4935 if (data_test->use_trace_keyword) 4936 action_name_test = data_test->synth_event_name; 4937 else 4938 action_name_test = data_test->action_name; 4939 4940 if (strcmp(action_name, action_name_test) != 0) 4941 return false; 4942 4943 if (data->handler == HANDLER_ONMATCH) { 4944 if (strcmp(data->match_data.event_system, 4945 data_test->match_data.event_system) != 0) 4946 return false; 4947 if (strcmp(data->match_data.event, 4948 data_test->match_data.event) != 0) 4949 return false; 4950 } else if (data->handler == HANDLER_ONMAX || 4951 data->handler == HANDLER_ONCHANGE) { 4952 if (strcmp(data->track_data.var_str, 4953 data_test->track_data.var_str) != 0) 4954 return false; 4955 } 4956 } 4957 4958 return true; 4959 } 4960 4961 4962 static void print_actions_spec(struct seq_file *m, 4963 struct hist_trigger_data *hist_data) 4964 { 4965 unsigned int i; 4966 4967 for (i = 0; i < hist_data->n_actions; i++) { 4968 struct action_data *data = hist_data->actions[i]; 4969 4970 if (data->handler == HANDLER_ONMATCH) 4971 print_onmatch_spec(m, hist_data, data); 4972 else if (data->handler == HANDLER_ONMAX || 4973 data->handler == HANDLER_ONCHANGE) 4974 print_track_data_spec(m, hist_data, data); 4975 } 4976 } 4977 4978 static void destroy_field_var_hists(struct hist_trigger_data *hist_data) 4979 { 4980 unsigned int i; 4981 4982 for (i = 0; i < hist_data->n_field_var_hists; i++) { 4983 kfree(hist_data->field_var_hists[i]->cmd); 4984 kfree(hist_data->field_var_hists[i]); 4985 } 4986 } 4987 4988 static void destroy_hist_data(struct hist_trigger_data *hist_data) 4989 { 4990 if (!hist_data) 4991 return; 4992 4993 destroy_hist_trigger_attrs(hist_data->attrs); 4994 destroy_hist_fields(hist_data); 4995 tracing_map_destroy(hist_data->map); 4996 4997 destroy_actions(hist_data); 4998 destroy_field_vars(hist_data); 4999 destroy_field_var_hists(hist_data); 5000 5001 kfree(hist_data); 5002 } 5003 5004 static int create_tracing_map_fields(struct hist_trigger_data *hist_data) 5005 { 5006 struct tracing_map *map = hist_data->map; 5007 struct ftrace_event_field *field; 5008 struct hist_field *hist_field; 5009 int i, idx = 0; 5010 5011 for_each_hist_field(i, hist_data) { 5012 hist_field = hist_data->fields[i]; 5013 if (hist_field->flags & HIST_FIELD_FL_KEY) { 5014 tracing_map_cmp_fn_t cmp_fn; 5015 5016 field = hist_field->field; 5017 5018 if (hist_field->flags & HIST_FIELD_FL_STACKTRACE) 5019 cmp_fn = tracing_map_cmp_none; 5020 else if (!field) 5021 cmp_fn = tracing_map_cmp_num(hist_field->size, 5022 hist_field->is_signed); 5023 else if (is_string_field(field)) 5024 cmp_fn = tracing_map_cmp_string; 5025 else 5026 cmp_fn = tracing_map_cmp_num(field->size, 5027 field->is_signed); 5028 idx = tracing_map_add_key_field(map, 5029 hist_field->offset, 5030 cmp_fn); 5031 } else if (!(hist_field->flags & HIST_FIELD_FL_VAR)) 5032 idx = tracing_map_add_sum_field(map); 5033 5034 if (idx < 0) 5035 return idx; 5036 5037 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5038 idx = tracing_map_add_var(map); 5039 if (idx < 0) 5040 return idx; 5041 hist_field->var.idx = idx; 5042 hist_field->var.hist_data = hist_data; 5043 } 5044 } 5045 5046 return 0; 5047 } 5048 5049 static struct hist_trigger_data * 5050 create_hist_data(unsigned int map_bits, 5051 struct hist_trigger_attrs *attrs, 5052 struct trace_event_file *file, 5053 bool remove) 5054 { 5055 const struct tracing_map_ops *map_ops = NULL; 5056 struct hist_trigger_data *hist_data; 5057 int ret = 0; 5058 5059 hist_data = kzalloc(sizeof(*hist_data), GFP_KERNEL); 5060 if (!hist_data) 5061 return ERR_PTR(-ENOMEM); 5062 5063 hist_data->attrs = attrs; 5064 hist_data->remove = remove; 5065 hist_data->event_file = file; 5066 5067 ret = parse_actions(hist_data); 5068 if (ret) 5069 goto free; 5070 5071 ret = create_hist_fields(hist_data, file); 5072 if (ret) 5073 goto free; 5074 5075 ret = create_sort_keys(hist_data); 5076 if (ret) 5077 goto free; 5078 5079 map_ops = &hist_trigger_elt_data_ops; 5080 5081 hist_data->map = tracing_map_create(map_bits, hist_data->key_size, 5082 map_ops, hist_data); 5083 if (IS_ERR(hist_data->map)) { 5084 ret = PTR_ERR(hist_data->map); 5085 hist_data->map = NULL; 5086 goto free; 5087 } 5088 5089 ret = create_tracing_map_fields(hist_data); 5090 if (ret) 5091 goto free; 5092 out: 5093 return hist_data; 5094 free: 5095 hist_data->attrs = NULL; 5096 5097 destroy_hist_data(hist_data); 5098 5099 hist_data = ERR_PTR(ret); 5100 5101 goto out; 5102 } 5103 5104 static void hist_trigger_elt_update(struct hist_trigger_data *hist_data, 5105 struct tracing_map_elt *elt, void *rec, 5106 struct ring_buffer_event *rbe, 5107 u64 *var_ref_vals) 5108 { 5109 struct hist_elt_data *elt_data; 5110 struct hist_field *hist_field; 5111 unsigned int i, var_idx; 5112 u64 hist_val; 5113 5114 elt_data = elt->private_data; 5115 elt_data->var_ref_vals = var_ref_vals; 5116 5117 for_each_hist_val_field(i, hist_data) { 5118 hist_field = hist_data->fields[i]; 5119 hist_val = hist_field->fn(hist_field, elt, rbe, rec); 5120 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5121 var_idx = hist_field->var.idx; 5122 tracing_map_set_var(elt, var_idx, hist_val); 5123 continue; 5124 } 5125 tracing_map_update_sum(elt, i, hist_val); 5126 } 5127 5128 for_each_hist_key_field(i, hist_data) { 5129 hist_field = hist_data->fields[i]; 5130 if (hist_field->flags & HIST_FIELD_FL_VAR) { 5131 hist_val = hist_field->fn(hist_field, elt, rbe, rec); 5132 var_idx = hist_field->var.idx; 5133 tracing_map_set_var(elt, var_idx, hist_val); 5134 } 5135 } 5136 5137 update_field_vars(hist_data, elt, rbe, rec); 5138 } 5139 5140 static inline void add_to_key(char *compound_key, void *key, 5141 struct hist_field *key_field, void *rec) 5142 { 5143 size_t size = key_field->size; 5144 5145 if (key_field->flags & HIST_FIELD_FL_STRING) { 5146 struct ftrace_event_field *field; 5147 5148 field = key_field->field; 5149 if (field->filter_type == FILTER_DYN_STRING) 5150 size = *(u32 *)(rec + field->offset) >> 16; 5151 else if (field->filter_type == FILTER_PTR_STRING) 5152 size = strlen(key); 5153 else if (field->filter_type == FILTER_STATIC_STRING) 5154 size = field->size; 5155 5156 /* ensure NULL-termination */ 5157 if (size > key_field->size - 1) 5158 size = key_field->size - 1; 5159 5160 strncpy(compound_key + key_field->offset, (char *)key, size); 5161 } else 5162 memcpy(compound_key + key_field->offset, key, size); 5163 } 5164 5165 static void 5166 hist_trigger_actions(struct hist_trigger_data *hist_data, 5167 struct tracing_map_elt *elt, void *rec, 5168 struct ring_buffer_event *rbe, void *key, 5169 u64 *var_ref_vals) 5170 { 5171 struct action_data *data; 5172 unsigned int i; 5173 5174 for (i = 0; i < hist_data->n_actions; i++) { 5175 data = hist_data->actions[i]; 5176 data->fn(hist_data, elt, rec, rbe, key, data, var_ref_vals); 5177 } 5178 } 5179 5180 static void event_hist_trigger(struct event_trigger_data *data, void *rec, 5181 struct ring_buffer_event *rbe) 5182 { 5183 struct hist_trigger_data *hist_data = data->private_data; 5184 bool use_compound_key = (hist_data->n_keys > 1); 5185 unsigned long entries[HIST_STACKTRACE_DEPTH]; 5186 u64 var_ref_vals[TRACING_MAP_VARS_MAX]; 5187 char compound_key[HIST_KEY_SIZE_MAX]; 5188 struct tracing_map_elt *elt = NULL; 5189 struct stack_trace stacktrace; 5190 struct hist_field *key_field; 5191 u64 field_contents; 5192 void *key = NULL; 5193 unsigned int i; 5194 5195 memset(compound_key, 0, hist_data->key_size); 5196 5197 for_each_hist_key_field(i, hist_data) { 5198 key_field = hist_data->fields[i]; 5199 5200 if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 5201 stacktrace.max_entries = HIST_STACKTRACE_DEPTH; 5202 stacktrace.entries = entries; 5203 stacktrace.nr_entries = 0; 5204 stacktrace.skip = HIST_STACKTRACE_SKIP; 5205 5206 memset(stacktrace.entries, 0, HIST_STACKTRACE_SIZE); 5207 save_stack_trace(&stacktrace); 5208 5209 key = entries; 5210 } else { 5211 field_contents = key_field->fn(key_field, elt, rbe, rec); 5212 if (key_field->flags & HIST_FIELD_FL_STRING) { 5213 key = (void *)(unsigned long)field_contents; 5214 use_compound_key = true; 5215 } else 5216 key = (void *)&field_contents; 5217 } 5218 5219 if (use_compound_key) 5220 add_to_key(compound_key, key, key_field, rec); 5221 } 5222 5223 if (use_compound_key) 5224 key = compound_key; 5225 5226 if (hist_data->n_var_refs && 5227 !resolve_var_refs(hist_data, key, var_ref_vals, false)) 5228 return; 5229 5230 elt = tracing_map_insert(hist_data->map, key); 5231 if (!elt) 5232 return; 5233 5234 hist_trigger_elt_update(hist_data, elt, rec, rbe, var_ref_vals); 5235 5236 if (resolve_var_refs(hist_data, key, var_ref_vals, true)) 5237 hist_trigger_actions(hist_data, elt, rec, rbe, key, var_ref_vals); 5238 } 5239 5240 static void hist_trigger_stacktrace_print(struct seq_file *m, 5241 unsigned long *stacktrace_entries, 5242 unsigned int max_entries) 5243 { 5244 char str[KSYM_SYMBOL_LEN]; 5245 unsigned int spaces = 8; 5246 unsigned int i; 5247 5248 for (i = 0; i < max_entries; i++) { 5249 if (stacktrace_entries[i] == ULONG_MAX) 5250 return; 5251 5252 seq_printf(m, "%*c", 1 + spaces, ' '); 5253 sprint_symbol(str, stacktrace_entries[i]); 5254 seq_printf(m, "%s\n", str); 5255 } 5256 } 5257 5258 static void hist_trigger_print_key(struct seq_file *m, 5259 struct hist_trigger_data *hist_data, 5260 void *key, 5261 struct tracing_map_elt *elt) 5262 { 5263 struct hist_field *key_field; 5264 char str[KSYM_SYMBOL_LEN]; 5265 bool multiline = false; 5266 const char *field_name; 5267 unsigned int i; 5268 u64 uval; 5269 5270 seq_puts(m, "{ "); 5271 5272 for_each_hist_key_field(i, hist_data) { 5273 key_field = hist_data->fields[i]; 5274 5275 if (i > hist_data->n_vals) 5276 seq_puts(m, ", "); 5277 5278 field_name = hist_field_name(key_field, 0); 5279 5280 if (key_field->flags & HIST_FIELD_FL_HEX) { 5281 uval = *(u64 *)(key + key_field->offset); 5282 seq_printf(m, "%s: %llx", field_name, uval); 5283 } else if (key_field->flags & HIST_FIELD_FL_SYM) { 5284 uval = *(u64 *)(key + key_field->offset); 5285 sprint_symbol_no_offset(str, uval); 5286 seq_printf(m, "%s: [%llx] %-45s", field_name, 5287 uval, str); 5288 } else if (key_field->flags & HIST_FIELD_FL_SYM_OFFSET) { 5289 uval = *(u64 *)(key + key_field->offset); 5290 sprint_symbol(str, uval); 5291 seq_printf(m, "%s: [%llx] %-55s", field_name, 5292 uval, str); 5293 } else if (key_field->flags & HIST_FIELD_FL_EXECNAME) { 5294 struct hist_elt_data *elt_data = elt->private_data; 5295 char *comm; 5296 5297 if (WARN_ON_ONCE(!elt_data)) 5298 return; 5299 5300 comm = elt_data->comm; 5301 5302 uval = *(u64 *)(key + key_field->offset); 5303 seq_printf(m, "%s: %-16s[%10llu]", field_name, 5304 comm, uval); 5305 } else if (key_field->flags & HIST_FIELD_FL_SYSCALL) { 5306 const char *syscall_name; 5307 5308 uval = *(u64 *)(key + key_field->offset); 5309 syscall_name = get_syscall_name(uval); 5310 if (!syscall_name) 5311 syscall_name = "unknown_syscall"; 5312 5313 seq_printf(m, "%s: %-30s[%3llu]", field_name, 5314 syscall_name, uval); 5315 } else if (key_field->flags & HIST_FIELD_FL_STACKTRACE) { 5316 seq_puts(m, "stacktrace:\n"); 5317 hist_trigger_stacktrace_print(m, 5318 key + key_field->offset, 5319 HIST_STACKTRACE_DEPTH); 5320 multiline = true; 5321 } else if (key_field->flags & HIST_FIELD_FL_LOG2) { 5322 seq_printf(m, "%s: ~ 2^%-2llu", field_name, 5323 *(u64 *)(key + key_field->offset)); 5324 } else if (key_field->flags & HIST_FIELD_FL_STRING) { 5325 seq_printf(m, "%s: %-50s", field_name, 5326 (char *)(key + key_field->offset)); 5327 } else { 5328 uval = *(u64 *)(key + key_field->offset); 5329 seq_printf(m, "%s: %10llu", field_name, uval); 5330 } 5331 } 5332 5333 if (!multiline) 5334 seq_puts(m, " "); 5335 5336 seq_puts(m, "}"); 5337 } 5338 5339 static void hist_trigger_entry_print(struct seq_file *m, 5340 struct hist_trigger_data *hist_data, 5341 void *key, 5342 struct tracing_map_elt *elt) 5343 { 5344 const char *field_name; 5345 unsigned int i; 5346 5347 hist_trigger_print_key(m, hist_data, key, elt); 5348 5349 seq_printf(m, " hitcount: %10llu", 5350 tracing_map_read_sum(elt, HITCOUNT_IDX)); 5351 5352 for (i = 1; i < hist_data->n_vals; i++) { 5353 field_name = hist_field_name(hist_data->fields[i], 0); 5354 5355 if (hist_data->fields[i]->flags & HIST_FIELD_FL_VAR || 5356 hist_data->fields[i]->flags & HIST_FIELD_FL_EXPR) 5357 continue; 5358 5359 if (hist_data->fields[i]->flags & HIST_FIELD_FL_HEX) { 5360 seq_printf(m, " %s: %10llx", field_name, 5361 tracing_map_read_sum(elt, i)); 5362 } else { 5363 seq_printf(m, " %s: %10llu", field_name, 5364 tracing_map_read_sum(elt, i)); 5365 } 5366 } 5367 5368 print_actions(m, hist_data, elt); 5369 5370 seq_puts(m, "\n"); 5371 } 5372 5373 static int print_entries(struct seq_file *m, 5374 struct hist_trigger_data *hist_data) 5375 { 5376 struct tracing_map_sort_entry **sort_entries = NULL; 5377 struct tracing_map *map = hist_data->map; 5378 int i, n_entries; 5379 5380 n_entries = tracing_map_sort_entries(map, hist_data->sort_keys, 5381 hist_data->n_sort_keys, 5382 &sort_entries); 5383 if (n_entries < 0) 5384 return n_entries; 5385 5386 for (i = 0; i < n_entries; i++) 5387 hist_trigger_entry_print(m, hist_data, 5388 sort_entries[i]->key, 5389 sort_entries[i]->elt); 5390 5391 tracing_map_destroy_sort_entries(sort_entries, n_entries); 5392 5393 return n_entries; 5394 } 5395 5396 static void hist_trigger_show(struct seq_file *m, 5397 struct event_trigger_data *data, int n) 5398 { 5399 struct hist_trigger_data *hist_data; 5400 int n_entries; 5401 5402 if (n > 0) 5403 seq_puts(m, "\n\n"); 5404 5405 seq_puts(m, "# event histogram\n#\n# trigger info: "); 5406 data->ops->print(m, data->ops, data); 5407 seq_puts(m, "#\n\n"); 5408 5409 hist_data = data->private_data; 5410 n_entries = print_entries(m, hist_data); 5411 if (n_entries < 0) 5412 n_entries = 0; 5413 5414 track_data_snapshot_print(m, hist_data); 5415 5416 seq_printf(m, "\nTotals:\n Hits: %llu\n Entries: %u\n Dropped: %llu\n", 5417 (u64)atomic64_read(&hist_data->map->hits), 5418 n_entries, (u64)atomic64_read(&hist_data->map->drops)); 5419 } 5420 5421 static int hist_show(struct seq_file *m, void *v) 5422 { 5423 struct event_trigger_data *data; 5424 struct trace_event_file *event_file; 5425 int n = 0, ret = 0; 5426 5427 mutex_lock(&event_mutex); 5428 5429 event_file = event_file_data(m->private); 5430 if (unlikely(!event_file)) { 5431 ret = -ENODEV; 5432 goto out_unlock; 5433 } 5434 5435 list_for_each_entry_rcu(data, &event_file->triggers, list) { 5436 if (data->cmd_ops->trigger_type == ETT_EVENT_HIST) 5437 hist_trigger_show(m, data, n++); 5438 } 5439 5440 if (have_hist_err()) { 5441 seq_printf(m, "\nERROR: %s\n", hist_err_str); 5442 seq_printf(m, " Last command: %s\n", last_hist_cmd); 5443 } 5444 5445 out_unlock: 5446 mutex_unlock(&event_mutex); 5447 5448 return ret; 5449 } 5450 5451 static int event_hist_open(struct inode *inode, struct file *file) 5452 { 5453 return single_open(file, hist_show, file); 5454 } 5455 5456 const struct file_operations event_hist_fops = { 5457 .open = event_hist_open, 5458 .read = seq_read, 5459 .llseek = seq_lseek, 5460 .release = single_release, 5461 }; 5462 5463 static void hist_field_print(struct seq_file *m, struct hist_field *hist_field) 5464 { 5465 const char *field_name = hist_field_name(hist_field, 0); 5466 5467 if (hist_field->var.name) 5468 seq_printf(m, "%s=", hist_field->var.name); 5469 5470 if (hist_field->flags & HIST_FIELD_FL_CPU) 5471 seq_puts(m, "cpu"); 5472 else if (field_name) { 5473 if (hist_field->flags & HIST_FIELD_FL_VAR_REF || 5474 hist_field->flags & HIST_FIELD_FL_ALIAS) 5475 seq_putc(m, '$'); 5476 seq_printf(m, "%s", field_name); 5477 } else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP) 5478 seq_puts(m, "common_timestamp"); 5479 5480 if (hist_field->flags) { 5481 if (!(hist_field->flags & HIST_FIELD_FL_VAR_REF) && 5482 !(hist_field->flags & HIST_FIELD_FL_EXPR)) { 5483 const char *flags = get_hist_field_flags(hist_field); 5484 5485 if (flags) 5486 seq_printf(m, ".%s", flags); 5487 } 5488 } 5489 } 5490 5491 static int event_hist_trigger_print(struct seq_file *m, 5492 struct event_trigger_ops *ops, 5493 struct event_trigger_data *data) 5494 { 5495 struct hist_trigger_data *hist_data = data->private_data; 5496 struct hist_field *field; 5497 bool have_var = false; 5498 unsigned int i; 5499 5500 seq_puts(m, "hist:"); 5501 5502 if (data->name) 5503 seq_printf(m, "%s:", data->name); 5504 5505 seq_puts(m, "keys="); 5506 5507 for_each_hist_key_field(i, hist_data) { 5508 field = hist_data->fields[i]; 5509 5510 if (i > hist_data->n_vals) 5511 seq_puts(m, ","); 5512 5513 if (field->flags & HIST_FIELD_FL_STACKTRACE) 5514 seq_puts(m, "stacktrace"); 5515 else 5516 hist_field_print(m, field); 5517 } 5518 5519 seq_puts(m, ":vals="); 5520 5521 for_each_hist_val_field(i, hist_data) { 5522 field = hist_data->fields[i]; 5523 if (field->flags & HIST_FIELD_FL_VAR) { 5524 have_var = true; 5525 continue; 5526 } 5527 5528 if (i == HITCOUNT_IDX) 5529 seq_puts(m, "hitcount"); 5530 else { 5531 seq_puts(m, ","); 5532 hist_field_print(m, field); 5533 } 5534 } 5535 5536 if (have_var) { 5537 unsigned int n = 0; 5538 5539 seq_puts(m, ":"); 5540 5541 for_each_hist_val_field(i, hist_data) { 5542 field = hist_data->fields[i]; 5543 5544 if (field->flags & HIST_FIELD_FL_VAR) { 5545 if (n++) 5546 seq_puts(m, ","); 5547 hist_field_print(m, field); 5548 } 5549 } 5550 } 5551 5552 seq_puts(m, ":sort="); 5553 5554 for (i = 0; i < hist_data->n_sort_keys; i++) { 5555 struct tracing_map_sort_key *sort_key; 5556 unsigned int idx, first_key_idx; 5557 5558 /* skip VAR vals */ 5559 first_key_idx = hist_data->n_vals - hist_data->n_vars; 5560 5561 sort_key = &hist_data->sort_keys[i]; 5562 idx = sort_key->field_idx; 5563 5564 if (WARN_ON(idx >= HIST_FIELDS_MAX)) 5565 return -EINVAL; 5566 5567 if (i > 0) 5568 seq_puts(m, ","); 5569 5570 if (idx == HITCOUNT_IDX) 5571 seq_puts(m, "hitcount"); 5572 else { 5573 if (idx >= first_key_idx) 5574 idx += hist_data->n_vars; 5575 hist_field_print(m, hist_data->fields[idx]); 5576 } 5577 5578 if (sort_key->descending) 5579 seq_puts(m, ".descending"); 5580 } 5581 seq_printf(m, ":size=%u", (1 << hist_data->map->map_bits)); 5582 if (hist_data->enable_timestamps) 5583 seq_printf(m, ":clock=%s", hist_data->attrs->clock); 5584 5585 print_actions_spec(m, hist_data); 5586 5587 if (data->filter_str) 5588 seq_printf(m, " if %s", data->filter_str); 5589 5590 if (data->paused) 5591 seq_puts(m, " [paused]"); 5592 else 5593 seq_puts(m, " [active]"); 5594 5595 seq_putc(m, '\n'); 5596 5597 return 0; 5598 } 5599 5600 static int event_hist_trigger_init(struct event_trigger_ops *ops, 5601 struct event_trigger_data *data) 5602 { 5603 struct hist_trigger_data *hist_data = data->private_data; 5604 5605 if (!data->ref && hist_data->attrs->name) 5606 save_named_trigger(hist_data->attrs->name, data); 5607 5608 data->ref++; 5609 5610 return 0; 5611 } 5612 5613 static void unregister_field_var_hists(struct hist_trigger_data *hist_data) 5614 { 5615 struct trace_event_file *file; 5616 unsigned int i; 5617 char *cmd; 5618 int ret; 5619 5620 for (i = 0; i < hist_data->n_field_var_hists; i++) { 5621 file = hist_data->field_var_hists[i]->hist_data->event_file; 5622 cmd = hist_data->field_var_hists[i]->cmd; 5623 ret = event_hist_trigger_func(&trigger_hist_cmd, file, 5624 "!hist", "hist", cmd); 5625 } 5626 } 5627 5628 static void event_hist_trigger_free(struct event_trigger_ops *ops, 5629 struct event_trigger_data *data) 5630 { 5631 struct hist_trigger_data *hist_data = data->private_data; 5632 5633 if (WARN_ON_ONCE(data->ref <= 0)) 5634 return; 5635 5636 data->ref--; 5637 if (!data->ref) { 5638 if (data->name) 5639 del_named_trigger(data); 5640 5641 trigger_data_free(data); 5642 5643 remove_hist_vars(hist_data); 5644 5645 unregister_field_var_hists(hist_data); 5646 5647 destroy_hist_data(hist_data); 5648 } 5649 } 5650 5651 static struct event_trigger_ops event_hist_trigger_ops = { 5652 .func = event_hist_trigger, 5653 .print = event_hist_trigger_print, 5654 .init = event_hist_trigger_init, 5655 .free = event_hist_trigger_free, 5656 }; 5657 5658 static int event_hist_trigger_named_init(struct event_trigger_ops *ops, 5659 struct event_trigger_data *data) 5660 { 5661 data->ref++; 5662 5663 save_named_trigger(data->named_data->name, data); 5664 5665 event_hist_trigger_init(ops, data->named_data); 5666 5667 return 0; 5668 } 5669 5670 static void event_hist_trigger_named_free(struct event_trigger_ops *ops, 5671 struct event_trigger_data *data) 5672 { 5673 if (WARN_ON_ONCE(data->ref <= 0)) 5674 return; 5675 5676 event_hist_trigger_free(ops, data->named_data); 5677 5678 data->ref--; 5679 if (!data->ref) { 5680 del_named_trigger(data); 5681 trigger_data_free(data); 5682 } 5683 } 5684 5685 static struct event_trigger_ops event_hist_trigger_named_ops = { 5686 .func = event_hist_trigger, 5687 .print = event_hist_trigger_print, 5688 .init = event_hist_trigger_named_init, 5689 .free = event_hist_trigger_named_free, 5690 }; 5691 5692 static struct event_trigger_ops *event_hist_get_trigger_ops(char *cmd, 5693 char *param) 5694 { 5695 return &event_hist_trigger_ops; 5696 } 5697 5698 static void hist_clear(struct event_trigger_data *data) 5699 { 5700 struct hist_trigger_data *hist_data = data->private_data; 5701 5702 if (data->name) 5703 pause_named_trigger(data); 5704 5705 tracepoint_synchronize_unregister(); 5706 5707 tracing_map_clear(hist_data->map); 5708 5709 if (data->name) 5710 unpause_named_trigger(data); 5711 } 5712 5713 static bool compatible_field(struct ftrace_event_field *field, 5714 struct ftrace_event_field *test_field) 5715 { 5716 if (field == test_field) 5717 return true; 5718 if (field == NULL || test_field == NULL) 5719 return false; 5720 if (strcmp(field->name, test_field->name) != 0) 5721 return false; 5722 if (strcmp(field->type, test_field->type) != 0) 5723 return false; 5724 if (field->size != test_field->size) 5725 return false; 5726 if (field->is_signed != test_field->is_signed) 5727 return false; 5728 5729 return true; 5730 } 5731 5732 static bool hist_trigger_match(struct event_trigger_data *data, 5733 struct event_trigger_data *data_test, 5734 struct event_trigger_data *named_data, 5735 bool ignore_filter) 5736 { 5737 struct tracing_map_sort_key *sort_key, *sort_key_test; 5738 struct hist_trigger_data *hist_data, *hist_data_test; 5739 struct hist_field *key_field, *key_field_test; 5740 unsigned int i; 5741 5742 if (named_data && (named_data != data_test) && 5743 (named_data != data_test->named_data)) 5744 return false; 5745 5746 if (!named_data && is_named_trigger(data_test)) 5747 return false; 5748 5749 hist_data = data->private_data; 5750 hist_data_test = data_test->private_data; 5751 5752 if (hist_data->n_vals != hist_data_test->n_vals || 5753 hist_data->n_fields != hist_data_test->n_fields || 5754 hist_data->n_sort_keys != hist_data_test->n_sort_keys) 5755 return false; 5756 5757 if (!ignore_filter) { 5758 if ((data->filter_str && !data_test->filter_str) || 5759 (!data->filter_str && data_test->filter_str)) 5760 return false; 5761 } 5762 5763 for_each_hist_field(i, hist_data) { 5764 key_field = hist_data->fields[i]; 5765 key_field_test = hist_data_test->fields[i]; 5766 5767 if (key_field->flags != key_field_test->flags) 5768 return false; 5769 if (!compatible_field(key_field->field, key_field_test->field)) 5770 return false; 5771 if (key_field->offset != key_field_test->offset) 5772 return false; 5773 if (key_field->size != key_field_test->size) 5774 return false; 5775 if (key_field->is_signed != key_field_test->is_signed) 5776 return false; 5777 if (!!key_field->var.name != !!key_field_test->var.name) 5778 return false; 5779 if (key_field->var.name && 5780 strcmp(key_field->var.name, key_field_test->var.name) != 0) 5781 return false; 5782 } 5783 5784 for (i = 0; i < hist_data->n_sort_keys; i++) { 5785 sort_key = &hist_data->sort_keys[i]; 5786 sort_key_test = &hist_data_test->sort_keys[i]; 5787 5788 if (sort_key->field_idx != sort_key_test->field_idx || 5789 sort_key->descending != sort_key_test->descending) 5790 return false; 5791 } 5792 5793 if (!ignore_filter && data->filter_str && 5794 (strcmp(data->filter_str, data_test->filter_str) != 0)) 5795 return false; 5796 5797 if (!actions_match(hist_data, hist_data_test)) 5798 return false; 5799 5800 return true; 5801 } 5802 5803 static int hist_register_trigger(char *glob, struct event_trigger_ops *ops, 5804 struct event_trigger_data *data, 5805 struct trace_event_file *file) 5806 { 5807 struct hist_trigger_data *hist_data = data->private_data; 5808 struct event_trigger_data *test, *named_data = NULL; 5809 int ret = 0; 5810 5811 if (hist_data->attrs->name) { 5812 named_data = find_named_trigger(hist_data->attrs->name); 5813 if (named_data) { 5814 if (!hist_trigger_match(data, named_data, named_data, 5815 true)) { 5816 hist_err("Named hist trigger doesn't match existing named trigger (includes variables): ", hist_data->attrs->name); 5817 ret = -EINVAL; 5818 goto out; 5819 } 5820 } 5821 } 5822 5823 if (hist_data->attrs->name && !named_data) 5824 goto new; 5825 5826 list_for_each_entry_rcu(test, &file->triggers, list) { 5827 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5828 if (!hist_trigger_match(data, test, named_data, false)) 5829 continue; 5830 if (hist_data->attrs->pause) 5831 test->paused = true; 5832 else if (hist_data->attrs->cont) 5833 test->paused = false; 5834 else if (hist_data->attrs->clear) 5835 hist_clear(test); 5836 else { 5837 hist_err("Hist trigger already exists", NULL); 5838 ret = -EEXIST; 5839 } 5840 goto out; 5841 } 5842 } 5843 new: 5844 if (hist_data->attrs->cont || hist_data->attrs->clear) { 5845 hist_err("Can't clear or continue a nonexistent hist trigger", NULL); 5846 ret = -ENOENT; 5847 goto out; 5848 } 5849 5850 if (hist_data->attrs->pause) 5851 data->paused = true; 5852 5853 if (named_data) { 5854 data->private_data = named_data->private_data; 5855 set_named_trigger_data(data, named_data); 5856 data->ops = &event_hist_trigger_named_ops; 5857 } 5858 5859 if (data->ops->init) { 5860 ret = data->ops->init(data->ops, data); 5861 if (ret < 0) 5862 goto out; 5863 } 5864 5865 if (hist_data->enable_timestamps) { 5866 char *clock = hist_data->attrs->clock; 5867 5868 ret = tracing_set_clock(file->tr, hist_data->attrs->clock); 5869 if (ret) { 5870 hist_err("Couldn't set trace_clock: ", clock); 5871 goto out; 5872 } 5873 5874 tracing_set_time_stamp_abs(file->tr, true); 5875 } 5876 5877 if (named_data) 5878 destroy_hist_data(hist_data); 5879 5880 ret++; 5881 out: 5882 return ret; 5883 } 5884 5885 static int hist_trigger_enable(struct event_trigger_data *data, 5886 struct trace_event_file *file) 5887 { 5888 int ret = 0; 5889 5890 list_add_tail_rcu(&data->list, &file->triggers); 5891 5892 update_cond_flag(file); 5893 5894 if (trace_event_trigger_enable_disable(file, 1) < 0) { 5895 list_del_rcu(&data->list); 5896 update_cond_flag(file); 5897 ret--; 5898 } 5899 5900 return ret; 5901 } 5902 5903 static bool have_hist_trigger_match(struct event_trigger_data *data, 5904 struct trace_event_file *file) 5905 { 5906 struct hist_trigger_data *hist_data = data->private_data; 5907 struct event_trigger_data *test, *named_data = NULL; 5908 bool match = false; 5909 5910 if (hist_data->attrs->name) 5911 named_data = find_named_trigger(hist_data->attrs->name); 5912 5913 list_for_each_entry_rcu(test, &file->triggers, list) { 5914 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5915 if (hist_trigger_match(data, test, named_data, false)) { 5916 match = true; 5917 break; 5918 } 5919 } 5920 } 5921 5922 return match; 5923 } 5924 5925 static bool hist_trigger_check_refs(struct event_trigger_data *data, 5926 struct trace_event_file *file) 5927 { 5928 struct hist_trigger_data *hist_data = data->private_data; 5929 struct event_trigger_data *test, *named_data = NULL; 5930 5931 if (hist_data->attrs->name) 5932 named_data = find_named_trigger(hist_data->attrs->name); 5933 5934 list_for_each_entry_rcu(test, &file->triggers, list) { 5935 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5936 if (!hist_trigger_match(data, test, named_data, false)) 5937 continue; 5938 hist_data = test->private_data; 5939 if (check_var_refs(hist_data)) 5940 return true; 5941 break; 5942 } 5943 } 5944 5945 return false; 5946 } 5947 5948 static void hist_unregister_trigger(char *glob, struct event_trigger_ops *ops, 5949 struct event_trigger_data *data, 5950 struct trace_event_file *file) 5951 { 5952 struct hist_trigger_data *hist_data = data->private_data; 5953 struct event_trigger_data *test, *named_data = NULL; 5954 bool unregistered = false; 5955 5956 if (hist_data->attrs->name) 5957 named_data = find_named_trigger(hist_data->attrs->name); 5958 5959 list_for_each_entry_rcu(test, &file->triggers, list) { 5960 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5961 if (!hist_trigger_match(data, test, named_data, false)) 5962 continue; 5963 unregistered = true; 5964 list_del_rcu(&test->list); 5965 trace_event_trigger_enable_disable(file, 0); 5966 update_cond_flag(file); 5967 break; 5968 } 5969 } 5970 5971 if (unregistered && test->ops->free) 5972 test->ops->free(test->ops, test); 5973 5974 if (hist_data->enable_timestamps) { 5975 if (!hist_data->remove || unregistered) 5976 tracing_set_time_stamp_abs(file->tr, false); 5977 } 5978 } 5979 5980 static bool hist_file_check_refs(struct trace_event_file *file) 5981 { 5982 struct hist_trigger_data *hist_data; 5983 struct event_trigger_data *test; 5984 5985 list_for_each_entry_rcu(test, &file->triggers, list) { 5986 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 5987 hist_data = test->private_data; 5988 if (check_var_refs(hist_data)) 5989 return true; 5990 } 5991 } 5992 5993 return false; 5994 } 5995 5996 static void hist_unreg_all(struct trace_event_file *file) 5997 { 5998 struct event_trigger_data *test, *n; 5999 struct hist_trigger_data *hist_data; 6000 struct synth_event *se; 6001 const char *se_name; 6002 6003 lockdep_assert_held(&event_mutex); 6004 6005 if (hist_file_check_refs(file)) 6006 return; 6007 6008 list_for_each_entry_safe(test, n, &file->triggers, list) { 6009 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6010 hist_data = test->private_data; 6011 list_del_rcu(&test->list); 6012 trace_event_trigger_enable_disable(file, 0); 6013 6014 se_name = trace_event_name(file->event_call); 6015 se = find_synth_event(se_name); 6016 if (se) 6017 se->ref--; 6018 6019 update_cond_flag(file); 6020 if (hist_data->enable_timestamps) 6021 tracing_set_time_stamp_abs(file->tr, false); 6022 if (test->ops->free) 6023 test->ops->free(test->ops, test); 6024 } 6025 } 6026 } 6027 6028 static int event_hist_trigger_func(struct event_command *cmd_ops, 6029 struct trace_event_file *file, 6030 char *glob, char *cmd, char *param) 6031 { 6032 unsigned int hist_trigger_bits = TRACING_MAP_BITS_DEFAULT; 6033 struct event_trigger_data *trigger_data; 6034 struct hist_trigger_attrs *attrs; 6035 struct event_trigger_ops *trigger_ops; 6036 struct hist_trigger_data *hist_data; 6037 struct synth_event *se; 6038 const char *se_name; 6039 bool remove = false; 6040 char *trigger, *p; 6041 int ret = 0; 6042 6043 lockdep_assert_held(&event_mutex); 6044 6045 if (glob && strlen(glob)) { 6046 last_cmd_set(param); 6047 hist_err_clear(); 6048 } 6049 6050 if (!param) 6051 return -EINVAL; 6052 6053 if (glob[0] == '!') 6054 remove = true; 6055 6056 /* 6057 * separate the trigger from the filter (k:v [if filter]) 6058 * allowing for whitespace in the trigger 6059 */ 6060 p = trigger = param; 6061 do { 6062 p = strstr(p, "if"); 6063 if (!p) 6064 break; 6065 if (p == param) 6066 return -EINVAL; 6067 if (*(p - 1) != ' ' && *(p - 1) != '\t') { 6068 p++; 6069 continue; 6070 } 6071 if (p >= param + strlen(param) - (sizeof("if") - 1) - 1) 6072 return -EINVAL; 6073 if (*(p + sizeof("if") - 1) != ' ' && *(p + sizeof("if") - 1) != '\t') { 6074 p++; 6075 continue; 6076 } 6077 break; 6078 } while (p); 6079 6080 if (!p) 6081 param = NULL; 6082 else { 6083 *(p - 1) = '\0'; 6084 param = strstrip(p); 6085 trigger = strstrip(trigger); 6086 } 6087 6088 attrs = parse_hist_trigger_attrs(trigger); 6089 if (IS_ERR(attrs)) 6090 return PTR_ERR(attrs); 6091 6092 if (attrs->map_bits) 6093 hist_trigger_bits = attrs->map_bits; 6094 6095 hist_data = create_hist_data(hist_trigger_bits, attrs, file, remove); 6096 if (IS_ERR(hist_data)) { 6097 destroy_hist_trigger_attrs(attrs); 6098 return PTR_ERR(hist_data); 6099 } 6100 6101 trigger_ops = cmd_ops->get_trigger_ops(cmd, trigger); 6102 6103 trigger_data = kzalloc(sizeof(*trigger_data), GFP_KERNEL); 6104 if (!trigger_data) { 6105 ret = -ENOMEM; 6106 goto out_free; 6107 } 6108 6109 trigger_data->count = -1; 6110 trigger_data->ops = trigger_ops; 6111 trigger_data->cmd_ops = cmd_ops; 6112 6113 INIT_LIST_HEAD(&trigger_data->list); 6114 RCU_INIT_POINTER(trigger_data->filter, NULL); 6115 6116 trigger_data->private_data = hist_data; 6117 6118 /* if param is non-empty, it's supposed to be a filter */ 6119 if (param && cmd_ops->set_filter) { 6120 ret = cmd_ops->set_filter(param, trigger_data, file); 6121 if (ret < 0) 6122 goto out_free; 6123 } 6124 6125 if (remove) { 6126 if (!have_hist_trigger_match(trigger_data, file)) 6127 goto out_free; 6128 6129 if (hist_trigger_check_refs(trigger_data, file)) { 6130 ret = -EBUSY; 6131 goto out_free; 6132 } 6133 6134 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); 6135 se_name = trace_event_name(file->event_call); 6136 se = find_synth_event(se_name); 6137 if (se) 6138 se->ref--; 6139 ret = 0; 6140 goto out_free; 6141 } 6142 6143 ret = cmd_ops->reg(glob, trigger_ops, trigger_data, file); 6144 /* 6145 * The above returns on success the # of triggers registered, 6146 * but if it didn't register any it returns zero. Consider no 6147 * triggers registered a failure too. 6148 */ 6149 if (!ret) { 6150 if (!(attrs->pause || attrs->cont || attrs->clear)) 6151 ret = -ENOENT; 6152 goto out_free; 6153 } else if (ret < 0) 6154 goto out_free; 6155 6156 if (get_named_trigger_data(trigger_data)) 6157 goto enable; 6158 6159 if (has_hist_vars(hist_data)) 6160 save_hist_vars(hist_data); 6161 6162 ret = create_actions(hist_data); 6163 if (ret) 6164 goto out_unreg; 6165 6166 ret = tracing_map_init(hist_data->map); 6167 if (ret) 6168 goto out_unreg; 6169 enable: 6170 ret = hist_trigger_enable(trigger_data, file); 6171 if (ret) 6172 goto out_unreg; 6173 6174 se_name = trace_event_name(file->event_call); 6175 se = find_synth_event(se_name); 6176 if (se) 6177 se->ref++; 6178 /* Just return zero, not the number of registered triggers */ 6179 ret = 0; 6180 out: 6181 if (ret == 0) 6182 hist_err_clear(); 6183 6184 return ret; 6185 out_unreg: 6186 cmd_ops->unreg(glob+1, trigger_ops, trigger_data, file); 6187 out_free: 6188 if (cmd_ops->set_filter) 6189 cmd_ops->set_filter(NULL, trigger_data, NULL); 6190 6191 remove_hist_vars(hist_data); 6192 6193 kfree(trigger_data); 6194 6195 destroy_hist_data(hist_data); 6196 goto out; 6197 } 6198 6199 static struct event_command trigger_hist_cmd = { 6200 .name = "hist", 6201 .trigger_type = ETT_EVENT_HIST, 6202 .flags = EVENT_CMD_FL_NEEDS_REC, 6203 .func = event_hist_trigger_func, 6204 .reg = hist_register_trigger, 6205 .unreg = hist_unregister_trigger, 6206 .unreg_all = hist_unreg_all, 6207 .get_trigger_ops = event_hist_get_trigger_ops, 6208 .set_filter = set_trigger_filter, 6209 }; 6210 6211 __init int register_trigger_hist_cmd(void) 6212 { 6213 int ret; 6214 6215 ret = register_event_command(&trigger_hist_cmd); 6216 WARN_ON(ret < 0); 6217 6218 return ret; 6219 } 6220 6221 static void 6222 hist_enable_trigger(struct event_trigger_data *data, void *rec, 6223 struct ring_buffer_event *event) 6224 { 6225 struct enable_trigger_data *enable_data = data->private_data; 6226 struct event_trigger_data *test; 6227 6228 list_for_each_entry_rcu(test, &enable_data->file->triggers, list) { 6229 if (test->cmd_ops->trigger_type == ETT_EVENT_HIST) { 6230 if (enable_data->enable) 6231 test->paused = false; 6232 else 6233 test->paused = true; 6234 } 6235 } 6236 } 6237 6238 static void 6239 hist_enable_count_trigger(struct event_trigger_data *data, void *rec, 6240 struct ring_buffer_event *event) 6241 { 6242 if (!data->count) 6243 return; 6244 6245 if (data->count != -1) 6246 (data->count)--; 6247 6248 hist_enable_trigger(data, rec, event); 6249 } 6250 6251 static struct event_trigger_ops hist_enable_trigger_ops = { 6252 .func = hist_enable_trigger, 6253 .print = event_enable_trigger_print, 6254 .init = event_trigger_init, 6255 .free = event_enable_trigger_free, 6256 }; 6257 6258 static struct event_trigger_ops hist_enable_count_trigger_ops = { 6259 .func = hist_enable_count_trigger, 6260 .print = event_enable_trigger_print, 6261 .init = event_trigger_init, 6262 .free = event_enable_trigger_free, 6263 }; 6264 6265 static struct event_trigger_ops hist_disable_trigger_ops = { 6266 .func = hist_enable_trigger, 6267 .print = event_enable_trigger_print, 6268 .init = event_trigger_init, 6269 .free = event_enable_trigger_free, 6270 }; 6271 6272 static struct event_trigger_ops hist_disable_count_trigger_ops = { 6273 .func = hist_enable_count_trigger, 6274 .print = event_enable_trigger_print, 6275 .init = event_trigger_init, 6276 .free = event_enable_trigger_free, 6277 }; 6278 6279 static struct event_trigger_ops * 6280 hist_enable_get_trigger_ops(char *cmd, char *param) 6281 { 6282 struct event_trigger_ops *ops; 6283 bool enable; 6284 6285 enable = (strcmp(cmd, ENABLE_HIST_STR) == 0); 6286 6287 if (enable) 6288 ops = param ? &hist_enable_count_trigger_ops : 6289 &hist_enable_trigger_ops; 6290 else 6291 ops = param ? &hist_disable_count_trigger_ops : 6292 &hist_disable_trigger_ops; 6293 6294 return ops; 6295 } 6296 6297 static void hist_enable_unreg_all(struct trace_event_file *file) 6298 { 6299 struct event_trigger_data *test, *n; 6300 6301 list_for_each_entry_safe(test, n, &file->triggers, list) { 6302 if (test->cmd_ops->trigger_type == ETT_HIST_ENABLE) { 6303 list_del_rcu(&test->list); 6304 update_cond_flag(file); 6305 trace_event_trigger_enable_disable(file, 0); 6306 if (test->ops->free) 6307 test->ops->free(test->ops, test); 6308 } 6309 } 6310 } 6311 6312 static struct event_command trigger_hist_enable_cmd = { 6313 .name = ENABLE_HIST_STR, 6314 .trigger_type = ETT_HIST_ENABLE, 6315 .func = event_enable_trigger_func, 6316 .reg = event_enable_register_trigger, 6317 .unreg = event_enable_unregister_trigger, 6318 .unreg_all = hist_enable_unreg_all, 6319 .get_trigger_ops = hist_enable_get_trigger_ops, 6320 .set_filter = set_trigger_filter, 6321 }; 6322 6323 static struct event_command trigger_hist_disable_cmd = { 6324 .name = DISABLE_HIST_STR, 6325 .trigger_type = ETT_HIST_ENABLE, 6326 .func = event_enable_trigger_func, 6327 .reg = event_enable_register_trigger, 6328 .unreg = event_enable_unregister_trigger, 6329 .unreg_all = hist_enable_unreg_all, 6330 .get_trigger_ops = hist_enable_get_trigger_ops, 6331 .set_filter = set_trigger_filter, 6332 }; 6333 6334 static __init void unregister_trigger_hist_enable_disable_cmds(void) 6335 { 6336 unregister_event_command(&trigger_hist_enable_cmd); 6337 unregister_event_command(&trigger_hist_disable_cmd); 6338 } 6339 6340 __init int register_trigger_hist_enable_disable_cmds(void) 6341 { 6342 int ret; 6343 6344 ret = register_event_command(&trigger_hist_enable_cmd); 6345 if (WARN_ON(ret < 0)) 6346 return ret; 6347 ret = register_event_command(&trigger_hist_disable_cmd); 6348 if (WARN_ON(ret < 0)) 6349 unregister_trigger_hist_enable_disable_cmds(); 6350 6351 return ret; 6352 } 6353 6354 static __init int trace_events_hist_init(void) 6355 { 6356 struct dentry *entry = NULL; 6357 struct dentry *d_tracer; 6358 int err = 0; 6359 6360 err = dyn_event_register(&synth_event_ops); 6361 if (err) { 6362 pr_warn("Could not register synth_event_ops\n"); 6363 return err; 6364 } 6365 6366 d_tracer = tracing_init_dentry(); 6367 if (IS_ERR(d_tracer)) { 6368 err = PTR_ERR(d_tracer); 6369 goto err; 6370 } 6371 6372 entry = tracefs_create_file("synthetic_events", 0644, d_tracer, 6373 NULL, &synth_events_fops); 6374 if (!entry) { 6375 err = -ENODEV; 6376 goto err; 6377 } 6378 6379 return err; 6380 err: 6381 pr_warn("Could not create tracefs 'synthetic_events' entry\n"); 6382 6383 return err; 6384 } 6385 6386 fs_initcall(trace_events_hist_init); 6387